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KM |
2D semiconductors-based synthetic superlattices for quantum simulation |
Finley |
- Research group
- Semiconductor Nanostructures and Quantum Systems
- Description
- The van der Waals stacking of different 2D crystals on top of each other has underpinned a recent series of remarkable discoveries including the demonstration of unconventional superconductivity in twisted bilayer graphene. In twisted bilayers of 2D semiconductors, the moiré superlattice pattern induced by the twist angle can localize excitons or electrons, yielding a periodic array of quantum-confined particles. Thanks to the strong many-body interactions inherent to 2D materials, such arrays have allowed the simulation of quantum many-body systems such as in correlated insulators, magnetism, and generalized Wigner crystals. [1]However, this approach to generating superlattices is subject to strict limitations on superlattice geometry from materials properties, and by extrinsic inhomogeneities introduced in the stacking process. [1]In this project, we pioneer a scalable and deterministic top-down approach to superimpose synthetic superlattices on an underlying bilayer system. Using this versatile technique, we study correlated phases, especially in configurations that cannot occur in natural matter.
[1] Wilson, N.P., Yao, W., Shan, J.et al.Excitons and emergent quantum phenomena in stacked 2D semiconductors.Nature(2021)
If you are interestedand you are looking to start a Master’s thesis project in SS or WS 2022 then please send an email to Dr. Nathan Wilson (Nathan.Wilson@wsi.tum.de), Amine Ben Mhenni (Amine.Ben-Mhenni@wsi.tum.de), and Prof. Jonathan Finley (Finley@wsi.tum.de). To read the full project advertisement please visit the link here
- Contact person
- Nathan Wilson
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AEP |
Absolute Photoemissionszeitbestimmung in Iodmethan und Iodethan |
Kienberger |
- Research group
- Laser and X-Ray Physics
- Description
-
Auch für KM! (English see below)
Diese Masterarbeit behandelt die experimentelle Bestimmung der absoluten Photoemissionszeit des I4d-Niveaus in Iodmethan und Iodethan für Photonenenergien zwischen 90eV und 120eV, und ist Teil einer größeren Messkampange die es zum Ziel hat die Photoemission von kleinen organischen Molekülen zu untersuchen, und damit besser zu verstehen.
Dabei eröffnet sich die Möglichkeit nicht nur die molekulare Umgebung, sondern auch die sog. giant resonance im I4d->Ef Kanal - ein Phänomen von großem Interesse in der Atomphysik - in der Zeitdomäne zu untersuchen. Die anregungsenergieabhängige Photoemissionszeit, welche in der Größenordnung von Attosekunden liegt (1as = 1e-18s), kann experimentell nur mit spezialisierten Methoden aus der Ultrakurzzeitphysik bestimmt werden: unser Aufbau implementiert das Prinzip der attosecond streak camera und ein kürzlich etabliertes absolutes Referenzierungsschema und ist damit nahezu einzigartig in der Welt.
Die experimentelle Arbeit wird durch numerische Untersuchungen der Photoemissionszeit der Moleküle ergänzt. Dabei werden etablierte Methoden für die Bestimmung der molekularen elektronischen Struktur, sowie für die Behandlung des Photoemissionsprozesses zum Einsatz kommen.
PDF-Version mit Referenzen:
https://www.groups.ph.tum.de/fileadmin/w00bya/e11/_my_direct_uploads/ad_german_reduced.pdf
This thesis concerns itself with the experimental assessment of the absolute timing of the I4d photoemissionfrom Iodomethane and Iodoethane for photon energies between 90eV and 120eV. It is part of a larger effort to understand the dynamics of photoemission from small molecules and offers the opportunity to study not only the influence of the molecular environment on the observable photoemission delay, but also the so-called giant resonance in the I4d->Ef photoemission in the time domain - a phenomenon of great interest in atomic physics.The excitation-energy dependent photoemission delay, which is on the order of attoseconds (1as = 1e-18s), can only be accessed in an experiment using sophisticated tools from the field of ultrafast physics: our setup implements the attosecond streak camera principle and an absolute referencing scheme established recently. It is one of the few in the world where such experiments can be conducted. The experimental work will be complemented by state-of-the-art numerical studies of the photoemission process in these molecules in order to complete the picture, where well-established methods will be applied for the determination of molecular electronic structure and the treatment of the photoionization process.
- Contact person
- Christian Schröder
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KM |
A finite temperature quantum algorithm for the Hubbard model |
Knap |
- Research group
- Collective Quantum Dynamics
- Description
- The goal of the thesis is to develop an analyze finite temperature algorithms for quantum computers. The field is quickly evolving. Please contact me to discuss a concrete project.
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AEP |
Atomistically thin semiconducting 2D materials and their optical properties |
Holleitner |
- Research group
- Nanotechnology and Nanomaterials
- Description
- Atomically thin van der Waals crystals form truly two-dimensional materials with remarkable quantum effects. Examples range from semi-metallic graphene to topological insulators and semiconducting materials with a thickness of only few atoms. The goal of this project is to characterize the fundamental symmetries of the underlying crystals and optical properties of such two-dimensional materials determined by optical means including Raman, photoluminescence (PL) and second harmonic generation (SHG) measurements, and to understand their optical properties particularly in two-dimensional heterostacks. The latter allow to build atomically thin field-effect, tunnelling, and photovoltaic devices.
Interest and good knowledge in solid state physics, semiconductor physics, Python programming, optoelectronics or nanofabrication is a plus, but certainly not a must.
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KTA |
Bau und Test neuer schneller Myontriggerdetektoren fuer das ATLAS-Experiment am Large Hadron Collider |
Kroha |
- Research group
- Max-Planck-Institute for Physics / Werner-Heisenberg-Institute (MPP)
- Description
- Fuer den Betrieb des ATLAS-Experiments bei sehr hohen Proton-Kollisionsraten am Large Hadron Collider (High-Luminosity LHC) werden neue sog. thin-gap resistive plate chambers (RPC) als Myontriggerdetektoren entwickelt. Derzeit findet der Technologietransfer in die Industrie fuer Massenproduktion der benoetigten grossen Detektorflaechen statt. Prototypendetektoren werden bei verschiedenen Firmen gefertigt und evaluuiert. Im Rahmen der Arbeit soll die Prototypenfertigung bei ausgewaehlten Firmen begleitet und der Test der Prototypen durchgefuehrt werden.
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KTA |
Bayesische Modellierung des GRB Nachleuchtens |
Greiner |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
- Gamma-ray bursts (GRBs) are transient objects bright in gamma-rays that result from an intense relativistic stellar explosion. As this explosion expands, it begins to sweep up the surrounding interstellar gas which shines X-rays (so-called afterglow). These X-rays act as unique probes of the gas within the GRBs local host galaxy as they are photo-electrically absorbed by that gas. Thus, the X-ray afterglow can be used to examine the group properties of galactic gas which can shed light on star formation and galaxy evolution. However, to date, no study of properly grouping and analyzing these gas properties exists.
This thesis will use real and simulated data and an existing Bayesian hierarchal modeling software to explore the group properties of interstellar gas via the simultaneous fitting of X-ray spectra obtained with the Swift X-ray telescope (XRT). Comparisons of existing methodologies will be performed to understand the trade-offs of analyzing individual x-ray spectra with existing x-ray analysis software (3ML) vs dedicated hierchcical models. Finally, the observed properties will be compared to predictions of galaxy formation simulations.
Technically, this thesis involves (i) understanding GRB afterglows and their use as interstellar gas probes, (ii) simulation of a population of GRBs with existing with existing software, (iii) analysis of big-data sets via hierarchical Bayesian modeling, (iv) acquisition and reduction of XRT x-ray spectra (v) communication of results and advanced data visualization.
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KTA |
Charakteriesierung der Eigenschaften neuer schneller Myondetektoren fuer das ATLAS-Experiment am Large Hadron Collider |
Kroha |
- Research group
- Max-Planck-Institute for Physics / Werner-Heisenberg-Institute (MPP)
- Description
- Fuer den Betrieb des ATLAS-Detektors bei sehr hohen Proton-Kollisionsraten am Large Hadron Collider (High-Luminosity LHC)werden neue schnelle und strahlungsbestaendige Myondetektoren gebaut. Die Eigenschaften dieser Detektoren sollen systematisch getestet und charakterisiert werden.
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KM |
Chemical reactions and spins |
Brandt |
- Research group
- Experimental Semiconductor Physics
- Description
- Elementary steps in chemical reaction pathways are difficult to disentangle. Often, such elementary steps involve radicals, molecules with unsaturated paramagnetic bonds. This allows to develop unique techniques monitoring their chemical reaction via spin selection rules based on the Pauli principle. You will develop highly sensitive magnetic resonance techniques measuring the charge transport in electrolytic cells to identify such spin-dependent reactions and, on the way, you will learn a lot about photocatalysis, electrochemistry and electron spin resonance. This Master’s thesis might be particularly interesting for students fascinated by renewable energies and motivated to work at the intersection of physics and chemistry.
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AEP |
Computational model for the growth of closed shells: how can self-assembled shapes be conserved during growth? |
Gerland |
- Research group
- Theory of Complex Bio-Systems
- Description
- The aim of this Master thesis is to use computer simulations as a tool to explore possible growth mechanisms for closed shells that form by self-assembly via out-of-equilibrium mechanisms. These shells could be the envelope of biological cells or of engineered biosynthetic containers made, e.g. of DNA or proteins. This thesis will focus on the conceptual kinetic mechanisms, on a coarse-grained level, rather than the detailed molecular implementation.
- Contact person
- Cesar Lopez Pastrana
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KTA |
Confinement of charged nanoparticles: Quadrupole Ion Trap - particle detection |
Eisenhauer |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
- Charged particles trapping and isolation, originally started in fundamental physics some 60 years ago, has nowadays numerous applications with interdisciplinary impact from astrophysics to biology. In laboratory astrophysics, ion traps are one of the few instruments allowing studies at conditions approaching those in the interstellar medium, where low temperatures (tens of K) and number densities (<10^10 cm^-3) prevail.
In this project the main goal is to develop an detection system for a charged and trapped nanoparticles of sizes ~500 nm in an cryogenic quadrupole ion trap. This is an experimental physics project, the participant will work to integrate the hardware (laser, detector, DAq) together with customised software in order to accomplish the task. This project will offer a deep insight into photon detection using APD (avalanche-photodiode), signal filtering and processing using Fourier transforms and data acquisition using customized hardware.
Contact:
Dr. Pavol Jusko
Prof. Paola Caselli
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KM |
Controlled Fabrication of Chiral Lead-Free Perovskites |
Deschler |
- Research group
- Experimental Semiconductor Physics
- Description
The Deschler group at the Walter Schottky Institute of TU Munich invites applications for
Bachelor/Master Projects on Controlled Fabrication of
Chiral Lead-Free Perovskites
The group
The Deschler group is an independent research group at Walter Schottky Institute of TU Munich, established through the DFG Emmy-Noether Program and an ERC starting Grant. Our research focuses on the ultrafast dynamics of functional materials and their applications energy applications. More information can be found on our website at https://www.wsi.tum.de/views/sub_group.php?group=Deschler&sub_page=home
Your projects
Hybrid organic inorganic perovskites are optoelectronic materials with tunable chemical and electronic structures. Incorporating chiral organic molecules into perovskite networks also attracts great attention due to their potential optical communication applications. Nevertheless, most reported chiral perovskite materials possess highly toxic Pb, which potentially limits their practical applications. In this project, your work would focus on introducing chiral organic molecules into hybrid lead-free perovskite, and grow corresponding high-performance single crystals and thin films. You will spearhead the design and fundamental understanding of novel functionality in materials. Specifically, you can work on one of following topics:
· Designing chiral lead-free perovskites with different chiral organic molecules
· Incorporating MA, FA, or Cs into chiral lead-free perovskites to get different layers samples
· Transition metal doping on chiral lead-free perovskites to acquire magnetic properties
During your Bachelor or Master project in our group, you will have the chance to gain hands-on experience in the solution-/vapor-based synthesis of novel functional materials, a range of state-of-the-art spectroscopic, optoelectronic and diffraction tools, as well as detailed understanding of the physics of functional semiconductors. Dedicated support from a PhD student or postdoc will be available during your project. You will be expected to make scientific discoveries and contribute to the dynamic atmosphere of our group.
Your Application
Applications should be sent to felix.deschler@tum.de. Please include your CV, and other related documents. Looking forward to your applications!
- Contact person
- Shangpu Liu
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AEP |
Convolutional neural networks and transfer learning for artefacts reduction in X-ray dark-field CT |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Grating-based X-ray dark-field (DF) imaging uses scattering of X-rays to create an image of an object, rather than conventional X-ray attenuation. The combination of X-ray scattering with imaging allows us to map information about structures that are much smaller than the resolution of the imaging system over a large field of view. X-ray dark-field imaging can be combined with computed tomography (CT) to create three-dimensional images of the scattering distribution inside an object. DF-CT was recently implemented for the first time into a clinical CT here at TUM
(https://www.bioengineering.tum.de/en/news/details/new-technology-for-clinical-ct-scans).
The goal of this project is to use convolutional neural networks (CNNs) to remove sampling artefacts in DF-CT images. Due to the unavailability of training data from the DF-CT machine, a technologically similar experimental setup and apply transfer learning will be used. The student will acquire, process and prepare training data, as well as train and apply CNNs.
Character of thesis work: experimental lab work/ data acquisition (50%) & computational/ image processing (50%)
Basic experience in image processing, CNNs, and/or Python programming are desirable.
For more information, please contact: Dr. Florian Schaff (florian.schaff@tum.de), or Prof. Franz Pfeiffer (franz.pfeiffer@tum.de).
- Contact person
- Florian Schaff
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BIO |
Cooking up life in the white smoker |
Alim |
- Research group
- Theory of Biological Networks
- Description
- White smokers are likely the cradle of life. Their caves and tunnels allow reactants to accumulate at catalytic sites to start the reactions at the origin of life. How do these catalytic sites form and grow with the smoker? You will grow two-dimensional smokers on a microfluidic chip and measure the smoker geometry from your data. You will learn about microfluidics, microscopy, Matlab, image analysis and the fluid physics of laminar flow in flow networks.
Prerequisites: Statistical physics and fascination for the wonders of nature.
Task 1 Learn and improve the experimental setup to control the microfluidic device for smoker formation
Task 2 Experimentally explore the morphologies of smokers as you vary inflow rate and inlet geometry
Task 3 Quantify smoker morphology with respect to the flow network geometry within the smoker. Built a hypothesis which physical conditions favor the formation of caves as catalytic sites.
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KTA |
CRESST: Freezing cold, deep underground, illuminating the dark (matter) |
Schönert |
- Research group
- Experimental Astro-Particle Physics
- Description
The CRESST (Cryogenic Rare-Event Search with Superconducting Thermometers) experiment operated at the Gran Sasso underground laboratory employs highly sensitive cryogenic detectors to the search for signals of the elusive dark matter particles, a main ingredient of the Universe whose nature is still unknown.
The energy thresholds reached in CRESST-III are the lowest in the field, making CRESST the most sensitive experiment to light dark matter. Optimisation of the tungsten thin-film thermometers and of the techniques for data analysis promise will further improve the energy threshold, which will significantly boost the physics reach of the experiment.
A student can contribute to:
- design, production and prototyping of new CRESST detectors in Munich
- development of high purity crystals
- development of new software tools for data analysis
- dark matter data analysis
and, if interested, can participate in the operation of the main experiment at Gran Sasso.
The theses can be carried out at the Chair for astroparticle physics of the Physics Department and/or at the Max-Planck-Institute for Physics (MPP). Supervision at the Physics Deptartment by Prof. Schönert / Dr. Strauss and at the MPP by Prof. Schönert / Dr. Federica Petricca. Please contact schoenert@ph.tum.de, raimund.strauss@ph.tum.de and petricca@mpp.mpg.de for further information.
We will organize a dedicated meeting for interested (bachelor) students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320 . Also Master students are welcome to join the meeting.
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AEP |
Design of a Scintillation Detector with Drift Monitoring via a Pulser System |
Märkisch |
- Research group
- Particle Physics at Low Energies
- Description
- The Proton and Electron Radiation Channel (PERC) facility, currently being set up at the FRM II, aims to measure the beta-asymmetry in neutron decay an order of magnitude more precisely to determine parameters of the Standard Model and to search for new physics beyond it. A system of superconducting coils guides the decay products towards the detector systems. PERC has one primary, downstream detector system and a secondary system located upstream, that will identify events with backscattered electrons from the primary detector. At first, the primary detector will be based on a fast plastic scintillator and photomultiplier tubes, similar to the detectors of previous experiments.
Calibrating the detectors is a key factor in achieving the precision aimed at. Radioactive sources with mono-energetic electrons serve for the calibration. A pulser system continuously monitors the detector’s drift with short, controlled light pulses. The pulser system, which includes a Kapustinsky pulser, a silicon photomultiplier and temperature sensors, is being controlled via an Arduino.
Within this project, the student will design and assemble the first primary detector for PERC and commission it including the pulser system. The performance of the detector will studied, including simulations based on Geant4.
- Contact person
- Karina Bernert
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KTA |
Development and Integration of Algorithms for Scientific Satellites |
Paul |
- Research group
- Hadronic Structure and Fundamental Symmetries
- Description
The Laboratory for Rapid Space Missions at the Origins Cluster of Excellence focuses on the development of scientific instruments for compact satellite platforms, called CubeSats. These nanosatellites enable the fast and modular deployment of complete, autonomous satellite systems at low cost.
Our research includes detectors to measure antimatter flux in low orbits, where scientific success relies on finding suitable algorithms and hardware platforms to filter and classify particle events. In addition, satellite-based science oftentimes requires precise determination of pointing direction, for which we are developing our own star tracker. We offer opportunities in the fields of data processing, machine learning and hardware design, which could include the following tasks:
- Simulation and modeling of particle fluxes
- Data processing for our antimatter detector, including neural networks, particle filters, and conventional classification approaches
- Image processing and optical engineering for attitude determination with our star tracker
- Identification of suitable hardware architectures and integration of your own software
- Work with VHDL, TensorFlow, Python, Zemax, Geant4, Altium Designer
What we expect from you:
- Capability for independent and self-reliant work
- Motivation, creativity and general interest in data processing and machine learning
- Hands-on mentality and ability to work in a small, interdisciplinary team
- Experience in one or more of the above-mentioned programming languages appreciated
Are you interested in working in an exciting and challenging environment with state-of-the-art technologies? Let’s have a talk!
- Contact person
- Peter Hinderberger
- Martin Losekamm
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AEP |
Development of a Star Tracker for Compact Scientific Satellites (topic is not available any more) |
Paul |
- Research group
- Hadronic Structure and Fundamental Symmetries
- Description
The Laboratory for Rapid Space Missions at the ORIGINS Cluster of Excellence develops scientific instruments for small-satellite missions. For the ComPol mission, which measures the polarization of X-rays emitted by the Cygnus X-1 binary system, a highly precise real-time determination of the satellite’s attitude is essential.
To achieve this, we aim to develop our own star-tracking system and tune the tracker’s properties exactly to the observed area in terms of source spectrum, light intensity, geometry, and spatial restrictions. Star trackers are very common instruments in satellite technology that compare an observed star formation with a database to calculate the exact spatial orientation of the satellite.
Your objectives include the optical design, assembly, calibration, and testing of a prototype system, the analysis of test data, and assistance with the mechanical layout, hardware design, and integration of a flight system. You will gain skills in optical engineering, including knowledge of the Zemax simulation software, programming and data analysis with Python, mechanical design, and general satellite technology at the interface between science and engineering. If successful, the system you design will be part of future missions to the ISS or on satellites!
We expect a high degree of self-responsibility, motivation, creativity, and a good share of curiosity. We offer work in a small, interdisciplinarian team, a broad combination of topics, and enough freedom for self-development and your own ideas. Knowledge of one or more of the above-mentioned fields is highly welcome, but not required.
Primary point of contact: Peter Hinderberger (peter.hinderberger@tum.de)
- Contact person
- Peter Hinderberger
- Martin Losekamm
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AEP |
Distortion correction for high-resolution quantitative X-ray imaging detectors |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
X-ray imaging detectors - in particular for high-resolution microscopy applications - may suffer from distortions, which degrade the image quality. This can have severe negative effects for quantitative applications, such as 3D micro-computed tomography. This project focuses on the characterisation of distortions of several X-ray imaging detectors at the Munich Compact Light Source, and the subsequent development of suitable correction methods.
Character of thesis work: mainly computational (image processing)
For more information, please contact: Martin Dierolf (martin.dierolf@tum.de), Johannes Melcher (johannes.melcher@tum.de), or Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Martin Dierolf
- Johannes Melcher
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AEP |
Effects of different anions and cations on electrode materials for applications in aqueous batteries |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
- Energy storage technologies are an indispensable element of the transition towards an eco-friendly society. Due to their low cost, scalability, and non-flammability, rechargeable aqueous sodium-ion batteries are a promising candidate for stationary applications, ranging from photovoltaic-powered private households to large-scale grid power buffers. This experimental master thesis project will aim at understanding, characterizing, and optimizing intercalation-type battery electrodes. The student will contribute to the ongoing investigation of fabrication methods, electrolyte composition, electrode substrates, active material composition, full-system prototyping, and performance characteristics like self-discharge and lifetime. The project will involve experimental laboratory training and hands-on work on battery systems, thereby conveying standard fabrication and characterization methods.
- Contact person
- Xaver Lamprecht
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AEP |
Electron-Selective ALD Protection Layers for Photoelectrochemical Hydrogen Evolution (topic is not available any more) |
Sharp |
- Research group
- Experimental Semiconductor Physics
- Description
- The Chair for Experimental Semiconductor Physics (Prof. Sharp) at the Walter Schottky Institute of the Technical University Munich (TUM) investigates novel materials for solar energy conversion applications. Our research explores different design strategies to improve the photoelectrochemical (PEC) activity and stability of energy materials under operation conditions. One promising path to PEC solar water splitting is the development of functional photoelectrodes from multi-junction solar cells. For this, new ultra-thin protection layers that provide corrosion protection while maintaining efficient charge transport need to be developed. This Master’s thesis focuses on the synthesis of electron-selective protection layers for PEC hydrogen evolution by means of atomic layer deposition (ALD). In this thesis, you will investigate and tune the chemical stability, optical and electrical properties of ALD grown metal-oxides. In the second phase of your thesis, you will employ the developed protection layers to prepare functional photoelectrodes from multi-junction solar cells with the goal of an improved PEC performance. In our group, you will have the chance to gain hands-on experience in atomic layer deposition and sophisticated physical vapor deposition methods, state-of-the-art spectroscopy and microscopy techniques, optoelectronic and diffraction techniques, as well as detailed understanding of the physics of functional semiconductors. Dedicated support from a PhD student will be available during your project. We are looking for a highly motivated student with background knowledge in semiconductor physics and/or photoelectrochemistry.
contact: Tim Rieth
- Contact person
- Tim Rieth
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KM |
Emergente (nichtlineare) Hydrodynamik in Ultrakalten Quantengasen |
Knap |
- Research group
- Collective Quantum Dynamics
- Description
- Isolated quantum matter can thermalize locally because the surrounding system can act as a path. We will study how hydrodynamics can emerge at late times in such systems. The field of quantum dynamics is quickly evolving. Please contact me directly to discuss a concrete project.
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KTA |
Entwicklung neuer schneller Ausleseelektronik fuer kuenftige Experimente der Hochenergiephysik an Collidern |
Kroha |
- Research group
- Max-Planck-Institute for Physics / Werner-Heisenberg-Institute (MPP)
- Description
- Fuer die Experimente an kuenftigen hochergetischen Beschleunigern wird neue schnelle Ausleseelektronik fuer die Myondetektoren in Form von Mikrochips entwickelt. Erste Prototypen sollen im Rahmen der Arbeit getestet und Verbesserungsmoeglichkeiten erarbeitet werden.
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AEP |
Estimation of Compton scattering in X-ray imaging using neural networks |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Compton scattering is one of the two primary interactions of X-rays with matter in X-ray imaging (next to photoelectric absorption). In contrast to photoelectric absorption, Compton scattering is an inelastic scattering process during which X-ray photons are deflected and transfer some of their energy to the interaction partner, typically an electron. As a consequence, photons may still reach the detector after Compton interaction. In X-ray imaging, this leads to a smoothly varying background, which reduces contrast and is detrimental to quantitative imaging. Furthermore, the Compton scatter background is not uniform, but instead depends on the materials and their distribution within an imaged object. This makes a straight-forward analytical correction difficult, and existing tools to estimate the Compton background are limited in their accuracy and applicability.
The goal of this thesis is to develop methods to a) estimate the Compton scattering background from simple radiographs, and b) correct these images for it. This will be done using machine learning, in particular convolutional neural networks. The student will generate Monte-Carlo simulations based on the Geant4 platform, design and train neural networks, apply them for Compton scatter correction on clinical radiography images, and compare the results to existing approaches.
The project involves mostly data preparation, and computational work (85%, primarily Python, with potentially some C++ for Geant4), as well as experimental data collection (15%). The project will involve collaboration with the Radiology department at the TUM Hospital Klinikum rechts der Isar.
Basic experience in scientific programming, Monte-Carlo simulations, neural networks, and/or X-ray imaging are desirable.
For more information, please contact: Dr. Florian Schaff (florian.schaff@tum.de), or Prof. Franz Pfeiffer (franz.pfeiffer@tum.de).
- Contact person
- Florian Schaff
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KM |
Exciton Physics of 2D layered Gallium Selenide (GaSe) |
Finley |
- Research group
- Semiconductor Nanostructures and Quantum Systems
- Description
- In contrast to the widely studied graphene and transition metal dichalcogenide (TMD) family of 2D layered semiconductors (MoS2, MoSe2, WS2, WSe2), the group-III monochalcogenides (III-MCs) MIIIX (MIII∈{In,Ga} and X∈{S,Se,Te}) are much less investigated but show remarkable physical properties and technological applications [1]. In particular, the bandgap of III-MCs can be tuned over the infrared to the ultra-violet spectral range as a function of layer thickness and the switch to direct gap as the number of layers increases from a single to a few (typically 3-7) layers is reported [2]. In our group, we study the intriguing chemical, electronic, optical and vibrionic properties of III-MCs materials. The aim of this project is to study the optical emission of mechanically exfoliated 2D Gallium Selenide (GaSe) obtained by standard industrial growth methods and compare it with films newly synthesized in our lab by molecular beam epitaxy (MBE).
You will learn how to create 2D devices by exfoliation and subsequent encapsulation, which is the process of covering a 2D materials of interest with another insulating 2D material for environmental protection. You will then develop a solid knowledge of fundamental spectroscopy by analyzing the excitonic lines from photoluminescence spectra in a cutting- edge laboratory. Additionally, you will correlate the results with differential reflectivity measurements and Raman spectroscopy in order to evaluate the absorption and band structure and the crystallographic structure, respectively.
While working on the project, you will learn about how to create and investigate devices with a new material, earn a deep understanding of recombination processes in 2D materials and develop data analysis and programming skills.
We are seeking highly motivated, hardworking students with an inclination for technical and optical lab work. Some experience with optical spectroscopy, 2D materials, cleanroom fabrication, scripting (Python) will be beneficial but not essential.
- Contact person
- Eugenio Zallo
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KM |
Exploration of Novel Photoactive Ternary Nitrides (topic is not available any more) |
Sharp |
- Research group
- Experimental Semiconductor Physics
- Description
- The Chair for Experimental Semiconductor Physics (Prof. Sharp) at the Walter Schottky Institute of the Technical University Munich (TUM) investigates novel photoelectrode materials for solar energy conversion applications. Our research explores new materials and different design strategies to improve the photoelectrochemical (PEC) activity and stability of energy materials under operation conditions. Here for, transition metal nitrides represent a versatile chemical space for creating new functional materials with tunable properties for a variety of applications, including e.g. solid-state lighting, integrated circuits, and photocatalysis.
This master thesis focuses in the first half on the synthesis and exploration of an unreported novel ternary nitride semiconductor with the goal to develop a new, efficient and stable photoanode. The second part will be dedicated to overcome stability and efficiency limiting effects such as oxidation and corrosion via the applications of surface passivation coatings and treatments. In our group, you will have the chance to gain hands-on experience in reactive magnetron co-sputtering and other sophisticated physical vapor deposition methods, state-of-the-art spectroscopy and microscopy techniques, optoelectronic and diffraction techniques, as well as detailed understanding of the physics of functional semiconductors. Dedicated support from a PhD student will be available during your project.
We are looking for a highly motivated student with background knowledge in semiconductor physics and/or photoelectrochemistry.
- Contact person
- Laura Wagner
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KM |
Exploring renewable energy systems with laser induced current transient thechnique |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
The advent of ultrafast lasers has paved the way and eased the investigations of mechanisms and phenomena, which hitherto were difficult to interrogate or measure. One of such mechanisms is the kinetics of the electrified electrode-electrolyte interface. The laser induced current transient (LICT) technique has proven to be a robust, unique, and indispensable tool for predicting to a high degree of accuracy the activity of reactions by identifying the so-called potential of maximum entropy (PME). The PME is the potential at the interface at which the degree of disorder peaks. At the PME, the reaction should proceed faster than at potentials remote from it. Thus, one can anticipate that the closer the PME is to the thermodynamic equilibrium potential of an electrocatalytic reaction, the faster the kinetics of this reaction should be. By employing the LICT technique, the PME measured at the electrode-electrolyte interface (i.e., Au polycrystalline electrode and Ar-saturated Na2SO4 electrolyte at a pH of 8) has been reported to be 0.58 V vs RHE. However, using Ar-saturated K2SO4 at the same pH yielded a PME value of 1.30 V vs RHE. Therefore, it is our considered view that this presents a stupendous opportunity to tailor the cation mixture of Na+ and K+ as electrolyte to obtain a PME value of 1.23 V vs RHE, the thermodynamic equilibrium potential of the oxygen reduction reaction (ORR). Hence, this presents the leeway for optimizing the activity towards the ORR via the tuning of the electrolyte cation concentration.
- Contact person
- Theophilus Kobina Sarpey
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AEP |
Fabrication of a superconducting coplanar transmission line for efficient coupling to rare earth spin ensembles |
Gross |
- Research group
- Technical Physics
- Description
- The rare earth spin ensembles are well established by now in the optical domain where the microwave states are used as an intermediate state to extend the storage time [1]. Number of purely microwave manipulations by spin ensembles is very limited and is bound to coupling of spin ensembles to microwave resonating structures [2], which allows amplifying the microwave signal and enhancing the interaction between the ions and the microwave field. The main disadvantage of using these resonating structures is their fixed frequencies and very small tuning range. Typically fabricated in a coplanar design, the superconducting resonators create strongly inhomogeneous distribution of the field within the spin ensemble, which results into largely detuned Rabi frequencies experienced by the spins.
Aim of this project is to fabricate novel design of microwave transmission line, which will allow for homogeneous distribution of the microwave field within the excited rare-earth spin ensemble, and at the same time, will not be bound to a specific frequency. This will allow realizing various spin manipulation schemes, which involve more than two energy levels (beyond Hahn-echo) and thus deploy complex spin-manipulation techniques.
We are looking for a highly motivated master student joining this project. Within the project, you will gain hands-on experience on design and fabrication of superconducting microwave structures. You will design and fabricate superconducting transmission line, which will then be tested at cryogenic conditions when coupled to rare earth spins ensembles.
[1] Kinos, A. et al. Roadmap for Rare-earth Quantum Computing. arXiv 2103.15743 (2021).
[2] Ranjan, V. et al. Multimode Storage of Quantum Microwave Fields in Electron Spins over 100 ms.
https://link.aps.org/doi/10.1103/PhysRevLett.125.210505 (2021).
- Contact person
- Nadezhda Kukharchyk
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KM |
Fabrication of a superconducting coplanar transmission line for efficient coupling to rare earth spin ensembles |
Gross |
- Research group
- Technical Physics
- Description
- The rare earth spin ensembles are well established by now in the optical domain where the microwave states are used as an intermediate state to extend the storage time [1]. Number of purely microwave manipulations by spin ensembles is very limited and is bound to coupling of spin ensembles to microwave resonating structures [2], which allows amplifying the microwave signal and enhancing the interaction between the ions and the microwave field. The main disadvantage of using these resonating structures is their fixed frequencies and very small tuning range. Typically fabricated in a coplanar design, the superconducting resonators create strongly inhomogeneous distribution of the field within the spin ensemble, which results into largely detuned Rabi frequencies experienced by the spins.
Aim of this project is to fabricate novel design of microwave transmission line, which will allow for homogeneous distribution of the microwave field within the excited rare-earth spin ensemble, and at the same time, will not be bound to a specific frequency. This will allow realizing various spin manipulation schemes, which involve more than two energy levels (beyond Hahn-echo) and thus deploy complex spin-manipulation techniques.
We are looking for a highly motivated master student joining this project. Within the project, you will gain hands-on experience on design and fabrication of superconducting microwave structures. You will design and fabricate superconducting transmission line, which will then be tested at cryogenic conditions when coupled to rare earth spins ensembles.
[1] Kinos, A. et al. Roadmap for Rare-earth Quantum Computing. arXiv 2103.15743 (2021).
[2] Ranjan, V. et al. Multimode Storage of Quantum Microwave Fields in Electron Spins over 100 ms.
https://link.aps.org/doi/10.1103/PhysRevLett.125.210505 (2021).
- Contact person
- Nadezhda Kukharchyk
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KM |
Fabrication of a superconducting transmission line in a planar design on a spin-doped crystalline membrane (topic is not available any more) |
Gross |
- Research group
- Technical Physics
- Description
- The rare earth spin ensembles are well established by now in the optical domain where the microwave states are used as an intermediate state to extend the storage time [1]. Number of purely microwave manipulations by spin ensembles is very limited and is bound to coupling of spin ensembles to microwave resonating structures [2], which allows amplifying the microwave signal and enhancing the interaction between the ions and the microwave field. The main disadvantage of using these resonating structures is their fixed frequencies and very small tuning range. Typically fabricated in a coplanar design, the superconducting resonators create strongly inhomogeneous distribution of the field within the spin ensemble, which results into largely detuned Rabi frequencies experienced by the spins.
Aim of this project is to fabricate novel design of microwave transmission lines on the crystal, which will allow for homogeneous distribution of the microwave field within the excited rare-earth spin ensemble, and at the same time, will not be bound to a specific frequency. This will allow realizing various spin manipulation schemes, which involve more than two energy levels (beyond Hahn-echo) and thus deploy complex spin-manipulation techniques.
[1] Kinos, A. et al. Roadmap for Rare-earth Quantum Computing. arXiv 2103.15743 (2021).
[2] Ranjan, V. et al. Multimode Storage of Quantum Microwave Fields in Electron Spins over 100 ms.
https://link.aps.org/doi/10.1103/PhysRevLett.125.210505 (2021).
- Contact person
- Nadezhda Kukharchyk
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AEP |
Fabrication of a superconducting transmission line resonator in a bad-cavity limit |
Gross |
- Research group
- Technical Physics
- Description
- The rare earth spin ensembles are well established by now in the optical domain where the microwave states are used as an intermediate state to extend the storage time [1]. Number of purely microwave manipulations by spin ensembles is very limited and is bound to coupling of spin ensembles to microwave resonating structures [2], which allows amplifying the microwave signal and enhancing the interaction between the ions and the microwave field. The main disadvantage of using these resonating structures is their fixed frequencies and very small tuning range. Typically fabricated in a coplanar design, the superconducting resonators create strongly inhomogeneous distribution of the field within the spin ensemble, which results into largely detuned Rabi frequencies experienced by the spins.
Aim of this project is to fabricate novel design of microwave transmission line resonator, which would work in a bad-cavity regime and will thus allow to couple to rare-earth spins at a larger badwidth. This will allow realizing various spin manipulation schemes, which involve more than two energy levels (beyond Hahn-echo) and thus deploy complex spin-manipulation techniques.
We are looking for a highly motivated master student joining this project. Within the project, you will gain hands-on experience on design and fabrication of superconducting microwave structures. You will design and fabricate superconducting resonating structure, which will then be tested at cryogenic conditions when coupled to rare earth spins ensembles.
[1] Kinos, A. et al. Roadmap for Rare-earth Quantum Computing. arXiv 2103.15743 (2021).
[2] Ranjan, V. et al. Multimode Storage of Quantum Microwave Fields in Electron Spins over 100 ms.
https://link.aps.org/doi/10.1103/PhysRevLett.125.210505 (2021).
- Contact person
- Thomas Luschmann
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KM |
Fabrication of a superconducting transmission line resonator in a bad-cavity limit |
Gross |
- Research group
- Technical Physics
- Description
- The rare earth spin ensembles are well established by now in the optical domain where the microwave states are used as an intermediate state to extend the storage time [1]. Number of purely microwave manipulations by spin ensembles is very limited and is bound to coupling of spin ensembles to microwave resonating structures [2], which allows amplifying the microwave signal and enhancing the interaction between the ions and the microwave field. The main disadvantage of using these resonating structures is their fixed frequencies and very small tuning range. Typically fabricated in a coplanar design, the superconducting resonators create strongly inhomogeneous distribution of the field within the spin ensemble, which results into largely detuned Rabi frequencies experienced by the spins.
Aim of this project is to fabricate novel design of microwave transmission line resonator, which would work in a bad-cavity regime and will thus allow to couple to rare-earth spins at a larger badwidth. This will allow realizing various spin manipulation schemes, which involve more than two energy levels (beyond Hahn-echo) and thus deploy complex spin-manipulation techniques.
We are looking for a highly motivated master student joining this project. Within the project, you will gain hands-on experience on design and fabrication of superconducting microwave structures. You will design and fabricate superconducting resonating structure, which will then be tested at cryogenic conditions when coupled to rare earth spins ensembles.
[1] Kinos, A. et al. Roadmap for Rare-earth Quantum Computing. arXiv 2103.15743 (2021).
[2] Ranjan, V. et al. Multimode Storage of Quantum Microwave Fields in Electron Spins over 100 ms.
https://link.aps.org/doi/10.1103/PhysRevLett.125.210505 (2021).
- Contact person
- Nadezhda Kukharchyk
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KM |
Fabrication of low-loss Josephson parametric devices |
Gross |
- Research group
- Technical Physics
- Description
- Superconducting Josephson devices represent one of the leading hardware platforms of modern quantum information processing. In particular, these devices often employ nonlinear parametric effects for tunable coupling schemes or quantum-limited amplification. Such effects can be also used in a multitude of quantum communication & sensing protocols. In this context, a particular challenge arises due to the fundamental requirement for minimizing losses in superconducting systems in order to preserve the fragile quantum nature of related microwave states. To this end, one needs to develop advanced routines for fabrication of low-loss Josephson parametric amplifiers & parametric couplers by exploring various surface treatment approaches or studying novel superconducting materials. The low-loss Josephson devices are to be used in our ongoing experiments towards experimental investigation of particular novel concepts, such as the quantum radar or remote entanglement distribution protocols.
This master thesis will involve designing superconducting parametric circuits, cleanroom fabrication, and characterization measurements of fabricated devices with an aim to employ these in microwave quantum communication & sensing experiments.
- Contact person
- Kirill Fedorov
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AEP |
Fabrication of low-loss Josephson parametric devices |
Gross |
- Research group
- Technical Physics
- Description
- Superconducting Josephson devices represent one of the leading hardware platforms of modern quantum information processing. In particular, these devices often employ nonlinear parametric effects for tunable coupling schemes or quantum-limited amplification. Such effects can be also used in a multitude of quantum communication & sensing protocols. In this context, a particular challenge arises due to the fundamental requirement for minimizing losses in superconducting systems in order to preserve the fragile quantum nature of related microwave states. To this end, one needs to develop advanced routines for fabrication of low-loss Josephson parametric amplifiers & parametric couplers by exploring various surface treatment approaches or studying novel superconducting materials. The low-loss Josephson devices are to be used in our ongoing experiments towards experimental investigation of particular novel concepts, such as the quantum radar or remote entanglement distribution protocols.
This master thesis will involve designing superconducting parametric circuits, cleanroom fabrication, and characterization measurements of fabricated devices with an aim to employ these in microwave quantum communication & sensing experiments.
- Contact person
- Kirill Fedorov
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AEP |
Finding Active Sites on Fuel Cell Catalysts with Scanning Tunneling Microscopy |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
- Currently, one of the main goals of our society is to reduce carbon emissions to stop the global temperature increase. A popular approach is to use hydrogen as a fuel as it would provide a sustainable and worldwide accessible energy system based on abundant resources and zero-emission. For the dream of a hydrogen economy to become reality, suitable and high-performing catalysts have to be identified and developed. Commonly, theoretical models and calculations are employed to gather information on the geometric structure of an optimal catalyst and its active sites. In our group, we use an experimental technique based on conventional scanning tunneling microscopy (STM) to in-situ identify active sites. The resulting insights can help to develop catalytic materials with optimal shapes and sizes and reduce the amount of rare materials needed for the construction of e.g. fuel cells, metal-air batteries, or electrolyzers.
The content of this experimental Master thesis is to apply the STM technique on different systems and to ideally achieve atomic resolution. A current collaboration will try to link our STM approach to machine learning for a more efficient evaluation or even prediction of the data. Especially haptic sensitivity will be helpful in this work. If you’re interested, please send an e-mail with a short introduction of your person and scientific background. We’re looking forward to meeting you!
Possible starting date: October 2021 or later
Contact: Regina Kluge (regina.kluge@ph.tum.de)
- Contact person
- Regina Kluge
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KM |
Fractonic quantum matter at low temperatures |
Knap |
- Research group
- Collective Quantum Dynamics
- Description
- Fractonic quantum matter possesses excitations with constrained mobility. In two dimensions, excitations can for example only move on one dimensional lines. The goal of this thesis is to study either with numerical or field theoretical techniques their ground state and dynamical properties. The field of fractions is quickly evolving. Please contact me directly to discuss a concrete project.
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AEP |
Generating small magnetic fields inside an open-end magnetic shielding with a superconducting solenoid magnet (topic is not available any more) |
Gross |
- Research group
- Technical Physics
- Description
- Coherence times of hyperfine transitions of rare earth spin ensembles reach seconds and hours. Particularly, this is possible due to cooling these ensembles down to ultra-low temperatures and taking advantage of Zero First-Oder Zeeman shift transition (ZEFOZ). These ZEFOZ transitions require very precise adjustment of magnetic field, in order to reach the very extremum point with the longest coherence time. Moreover, employing ZEFOZ transition allows working at near-zero magnetic fields [1], which paves the way towards the quantum memory for the superconducting qubits.
To have a precise control of the magnetic field at near zero field range, it is necessary to remove or strongly reduce any external background magnetic fields. Alternative way would be to confine the magnetic field and align them along a single axis. Controllably applying another external magnetic field along the same axis, would allow accessing a desired operational point with lowest coherence in a highly controllable way.
The goal of this master project is to build such a semi-shielded solenoid magnet with a sample space, which will allow for reaching a desired ZEFOZ point at near-zero magnetic field.
We are looking for a highly motivated master student joining this project. Within the project, you will learn about practical realization of magnetic shielding and superconducting magnets. You will design an experimental magnetically controlled sample space for spin-ensemble quantum memories.
[1] Y.-H. Chen et al. „Coupling erbium spins to a three-dimensional superconducting cavity at zero magnetic field”, Phys. Rev. B, vol. 94, p. 075117, Aug 2016
- Contact person
- Nadezhda Kukharchyk
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KM |
Generating small magnetic fields inside an open-end magnetic shielding with a superconducting solenoid magnet (topic is not available any more) |
Gross |
- Research group
- Technical Physics
- Description
- Coherence times of hyperfine transitions of rare earth spin ensembles reach seconds and hours. Particularly, this is possible due to cooling these ensembles down to ultra-low temperatures and taking advantage of Zero First-Oder Zeeman shift transition (ZEFOZ). These ZEFOZ transitions require very precise adjustment of magnetic field, in order to reach the very extremum point with the longest coherence time. Moreover, employing ZEFOZ transition allows working at near-zero magnetic fields [1], which paves the way towards the quantum memory for the superconducting qubits.
To have a precise control of the magnetic field at near zero field range, it is necessary to remove or strongly reduce any external background magnetic fields. Alternative way would be to confine the magnetic field and align them along a single axis. Controllably applying another external magnetic field along the same axis, would allow accessing a desired operational point with lowest coherence in a highly controllable way.
The goal of this master project is to build such a semi-shielded solenoid magnet with a sample space, which will allow for reaching a desired ZEFOZ point at near-zero magnetic field.
We are looking for a highly motivated master student joining this project. Within the project, you will learn about practical realization of magnetic shielding and superconducting magnets. You will design an experimental magnetically controlled sample space for spin-ensemble quantum memories.
[1] Y.-H. Chen et al. „Coupling erbium spins to a three-dimensional superconducting cavity at zero magnetic field”, Phys. Rev. B, vol. 94, p. 075117, Aug 2016
- Contact person
- Nadezhda Kukharchyk
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AEP |
GRAVITY Wide Upgrade - Entwicklung der Systemkontrollarchitektur fuer die optische differenzielle Pfadlängenkompensation (topic is not available any more) |
Eisenhauer |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
GRAVITY is a second generation interferometric instrument in operation ESO’s Paranal Observatory, Chile. Connected to four 8m telescopes, it combines their light to obtain imaging, spectroscopic and astrometric information at the highest spatial resolutions currently available in infrared astronomy. The master project will focus on the upgrade of GRAVITY ravity with new active, optical delay lines to co-phase the light of the different telescopes. Specifically the student will integrate, test and characterize the combination of a high precision linear stage and a piezo-electrically driven mirror mount in combination with a laser distance metrology system to achieve 20 nm optical path length stability. Topics will cover mechano-optical design, control system engineering and interface design and the student should expect to spend a significant fraction of their time in the laboratories at MPE. This thesis presents a rare opportunity to support and witness a state of the art instrumental project for the Very Large Telescope all the way from the design phase to its implementation.
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KTA |
GRAVITY WIDE upgrade - Implementierung der Systemkontrolle und Metrologie für einen optische differenzielle Pfadlängenkompensation (topic is not available any more) |
Eisenhauer |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
GRAVITY is a second generation interferometric instrument in operation ESO’s Paranal Observatory, Chile. Connected to four 8m telescopes, it combines their light to obtain imaging, spectroscopic and astrometric information at the highest spatial resolutions currently available in infrared astronomy. The master project will focus on the upgrade of GRAVITY ravity with new active, optical delay lines to co-phase the light of the different telescopes. Specifically the student will integrate, test and characterize the combination of a high precision linear stage and a piezo-electrically driven mirror mount in combination with a laser distance metrology system to achieve 20 nm optical path length stability. Topics will cover mechano-optical design, control system engineering and interface design and the student should expect to spend a significant fraction of their time in the laboratories at MPE. This thesis presents a rare opportunity to support and witness a state of the art instrumental project for the Very Large Telescope all the way from the design phase to its implementation.
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BIO |
Growing shapes: Kinetics of integrating cell wall material into the envelope of a growing cell |
Gerland |
- Research group
- Theory of Complex Bio-Systems
- Description
- The aim of this Master thesis is to explore different modes of cell wall growth, which is locally controlled by enzymes but has a global effect on the shape of the cell. Which schemes of enzymatic action permit stably growing cell shapes? And which ones can mimick the observed growth behavior of different bacterial species? These fundamental questions are surpisingly largely open, partially due to the difficulty of experimentally determining which local properties of the cell wall affect the enzymatic activity. In light of this experimental barrier, conceptual theoretical models can classify different plausible schemes by their large-scale behavior, which is more easily observed experimentally. This thesis will combine simulations of stochastic models for growing shapes with simple analytical toy models to address some of the open questions.
- Contact person
- Cesar Lopez Pastrana
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AEP |
High efficiency next generation organic solar cells |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
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Next generation organic solar cells are solar cells beyond the silicon type photovoltaic devices. Organic solar cells have reached efficiencies in the champion solar cells well above 18%. Key element of such solar cells is the highly designed active layer, which transfers light into separated charge carriers. Aim of this experimental project is the preparation and full characterization of an active layer for high performance organic photovoltaic devices to further understand the fundamental correlation between morphology and solar cell performance. In this work a novel efficiency record-setting system will be investigated regarding the influence of an additional third component, in our case, either solvent additive or polymer. The project will involve a literature review, sample preparation, photovoltaic device fabrication and photoluminescent measurements. The focus is the usage of advanced scattering techniques for the determination of structural length scales of the active layer in the solar cell.
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AEP |
High-sensitivity grating-based phase-contrast imaging at the Munich Compact Light Source - Computational Part |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Using phase-contrast as alternative imaging contrast for X-rays can considerably improve the imaging results for biomedical specimens. This project will focus on the development of an algorithmic framework for a high-sensitivity and high-resolution grating-based phase-contrast micro-tomography setup at the Munich Compact Light Source for investigating soft-tissue biomedical samples, such biopsies.
Character of thesis work: mainly computational (image processing/ reconstruction)
For more information, please contact: Martin Dierolf (martin.dierolf@tum.de), Johannes Brantl (johannes.brantl@tum.de), or Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Martin Dierolf
- Johannes Brantl
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AEP |
High-sensitivity grating-based phase-contrast imaging at the Munich Compact Light Source - Experimental Part |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
- Using phase-contrast as alternative imaging contrast for X-rays can considerably improve the imaging results for biomedical specimens. This project will focus on the experimental construction of a high-sensitivity and high-resolution grating-based phase-contrast micro-tomography setup at the Munich Compact Light Source for investigating soft-tissue biomedical samples, such as biopsies.
Character of thesis work: mainly experimental
For more information, please contact: Martin Dierolf (martin.dierolf@tum.de), Johannes Brantl (johannes.brantl@tum.de), or Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Martin Dierolf
- Johannes Brantl
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KM |
Hochauflösende magnetische Mikroskopie unter Verwendung des spitzenverstärkten Anomalen-Nernst-Effekts |
Back |
- Research group
- Experimental Physics of Functional Spin Systems
- Description
- We want to use a tip-enhanced near-field microscope to enable high-resolution magnetic microscopy. In this experiment, the tip of a force microscope is illuminated with a laser and thus a large temperature gradient is generated locally (via the field increase at the tip). The temperature gradient generates an anomalous Nernst voltage locally, which can be detected via electrical contacts on the ferromagnetic nanostructure. With this method, it should be possible to realise magnetic microscopy with a spatial resolution of 20 nm.
- Contact person
- Christian Riedel
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AEP |
How our veins adapt |
Alim |
- Research group
- Theory of Biological Networks
- Description
- Our vein network is important for transporting oxygen and other important resources in our body. Our vein network is not static but continuously adapts its structure and the thickness of individual veins. What laws govern the dynamics of individual veins? What role does the flow in the cores play? You will analyse data from vein networks on a microfluidic chip in order to quantitatively record the dynamics of the veins. For this purpose, you will further develop image analysis methods and adapt them to our completely new data of veins.
Task 1 Learn how to work with the machine-learning based image analysis tool ilastik
Task 2 Quantify vein diameters and vein network morphologies from existing vein microfluidic data
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AEP |
Hybrid quantum teleportation |
Gross |
- Research group
- Technical Physics
- Description
- Microwave quantum communication is a novel field of science and technology, where one exploits quantum properties of propagating microwave signals to achieve quantum advantage in various communication scenarios. Here, a particularly important protocol is quantum teleportation, where one bypasses fundamental limitations on fidelity of transferred quantum states by exploiting shared entanglement. In this context, an open challenge is teleportation of the most exotic, non-Gaussian, quantum states, such as Fock or Schrödinger cat states, with the help of Gaussian entangled states. In theory, this problem can be addressed by using non-deterministic approaches or incorporating non-Gaussian operations in the teleportation protocol.
This master thesis will focus on a theory analysis & numerical simulation of quantum microwave teleportation of non-Gaussian quantum states. Later stages of this master project may include experimental investigation of proof-of-principle hybrid quantum teleportation protocols based on superconducting quantum circuits in the cryogenic environment.
- Contact person
- Kirill Fedorov
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AEP |
Implementation of a grating-based interferometer for X-ray vector radiography at the Munich Compact Light Source |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Grating-based X-ray dark-field (DF) imaging uses scattering of X-rays to create an image of an object, rather than conventional X-ray attenuation. The combination of X-ray scattering with imaging allows us to map information about structures that are much smaller than the resolution of the imaging system over a large field of view. The fact that the used gratings typically are one-dimensional can be leveraged to obtain an orientation dependent dark-field signal in a technique called X-ray vector radiography (XVR). Applications of XVR include the determination of the fibre orientation in reinforced composite materials, or characterization of the anisotropic structure in trabecular bones.
The goal of this project is to implement an experimental XVR setup at the Munich Compact Light Source (MuCLS - https://www.bioengineering.tum.de/en/central-building/munich-compact-light-source). The student will help with the design, implementation, and characterization of the X-ray grating interferometer setup, and conduct their own XVR experiments.
Character of thesis work: experimental lab work/ controls/ data acquisition (50%) & computational/ simulation/image processing (50%)
Basic experience in X-ray imaging, and/or Python programming are desirable.
For more information, please contact: Dr. Florian Schaff (florian.schaff@tum.de), or Prof. Franz Pfeiffer (franz.pfeiffer@tum.de).
- Contact person
- Florian Schaff
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KM |
Josephson Ring Modulator Coupler Measurement |
Gross |
- Research group
- Technical Physics
- Description
- Adiabatic Quantum Computation aims at finding the solution for optimization problems by adiabatic Hamiltonian evolution. Physically, the problems are encoded in the so-called Ising Hamiltonian and the task is to find the state of lowest energy, the ground state. As can be seen in the Ising Hamiltonian, all spins have to interact with all other spins to be able to deal with general optimization problems. In practice, achieving this all-to-all connectivity is a hard task. A particularly promising approach is the so-called Lechner-Hauke-Zoller architecture, which we want to implement with superconducting circuits. There, one of the fundamental building block is a Josephson ring modulator coupler featuring the strong ZZ interaction.
Your task will be the experimental characterization of the JRM coupler. You will analyze the ZZ interaction strength in the on-state and the parasitic cross-talk between the qubits in the off-state of the coupler. Ultimately, you will realize a simple quantum annealing protocol.
- Contact person
- Yuki Nojiri
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BIO |
Koordinierung von Informationen innerhalb eines nicht-neuralen Organismus (topic is not available any more) |
Alim |
- Research group
- Theory of Biological Networks
- Description
- The smart slime mould Physarum polycephalum is renowned for its ability to solve complex problems - lacking any brain nor organising center. Instead the giant cell that makes up the entire organism houses thousands of nuclei that altogether control the organisms behaviour. How do nuclei interact to mount behaviour? Do they compete, cooperate or happily ignore each other? You will follow nuclei dynamics with fluorescence microscopy during the organism’s response to an environmental challenge. Quantification of individual nuclei trajectories will inform you if nuclei act individually or cooperatively during behavioural response. You will have the opportunity to discuss your findings with biologists and applied mathematicians throughout your project.
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KTA |
LEGEND: Why does matter prevail over antimatter in today's Universe? |
Schönert |
- Research group
- Experimental Astro-Particle Physics
- Description
- Neutrinos were discovered in 1956, but only at the turn of the millennium was it experimentally proven that the three known neutrino types can convert into one another. These flavor oscillations are possible only if neutrinos have nonzero mass, which is currently the only established contradiction to the standard model (SM) of particle physics.
From tritium beta decay experiments and cosmological observations, we know that their masses are very small—less than 10^{-5} of the electron mass. Neutrinos are the only fundamental spin-1/2 particles (fermions) without electric charge. As a consequence, they might be Majorana fermions, particles identical to their antiparticles.
This is a key ingredient for the explanation for why matter is so much more abundant than antimatter in today’s Universe and why neutrinos are so much lighter than the other elementary particles.
Majorana neutrinos would lead to nuclear decays that violate lepton number conservation and are therefore forbidden in the Standard Model of particle physics. The so-called neutrinoless double-beta (0nbb) decay simultaneously transforms two neutrons inside a nucleus into two protons with the emission of two electrons. The LEGEND-200 experiment, currently under commissioning at the Italian Gran Sasso underground laboratory aims to be the first experiment to probe half-lives beyond 1E27 years.
We offer the opportunity to carry out exciting experimental BSc (and MSc) theses with a focus on:
- liquid argon detector development: SiPMs, VUV light detection and wavelength shifting, xenon-doping, trace analysis;
- germanium detectors: detector design, modeling of signal generation, pulse shape analysis, surface event discrimination;
- new software tools and algorithms: classical techniques, machine learning methods;
- data analysis: rare line searches, exotic decays, time and spatial coincidence searches;
- Monte Carlo simulations: light propagation and detection in liquid argon, gamma rays from radioactive decays, isotope production deep underground by cosmic rays;
and, if interested, can participate in the operation of the main experiment at Gran Sasso.
You would be fully integrated into the research team and would work closely together with our international partners.
The theses can be carried out at the Chair for astroparticle physics of the Physics Department. Supervision at the Physics Deptartment by Prof. Schönert and his team. Please contact schoenert@ph.tum.de for further information.
We will organize a dedicated meeting for interested bachelor students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320 . Also Master students are welcome to join.
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AEP |
Lightweight Organic Solar Cells as Alternative to Nuclear Batteries for Deep Space Power Generation |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- The exploration of the outer solar system so far relied heavily on the use of scarce, highly radioactive plutonium stockpiles for power generation, as traditional solar cells have a too low power-to-mass ratio in low light environments to be suitable for those missions. Latest advances in organic solar cells now open up the possibility of utilising them on lightweight foils as photovoltaic solar sails for efficient power generation in low solar irradiation conditions. We have just recently successfully demonstrated the first power generation of organic solar cells on a suborbital space-mission, featuring our in-house developed "Organic and Hybrid Solar Cells In Space" (OHSCIS) experiment. While this demonstration still employed a more traditional, non weight-optimised solar cell design for more typical earth-bound applications, your task will now be to further optimise the design and material selection to reduce the mass of our organic solar cells for our next upcoming space-mission. The solar cells you build will then take part in this mission and be launched into space.
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KM |
Machinelles Lernen zur Molekulardynamik |
Egger |
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KTA |
Massenabschätzungen für kompakte Objekte in Röntgen-Doppelsystemen mit niedrigen Massen über optische und nahe infrarote Ellipsoidale Variationen (topic is not available any more) |
Greiner |
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KM |
Masterarbeit: Mechanisches Strukturieren von Elektroden für Lithium-Ionen-Batterien |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
- Ausgangssituation
-----------------
Die kostengünstige Produktion von leistungsstarken Lithium-Ionen-Batterien stellt eine der größten Herausforderungen bei der Marktdurchdringung der Elektromobilität dar. Durch Laser-Strukturieren von Elektroden konnte zwar bereits eine große Leistungssteigerung erzielt werden, doch der geringe Durch-
satz und das Abtragen von Aktivmaterial sorgen für hohe Prozesskosten. Der neuartige Prozess des mechanischen
Strukturierens birgt großes Potential, die Kosten der Produktion bei gesteigerter Produktqualität zu senken.
Zielsetzung
--------------
Im Rahmen der Masterarbeit soll untersucht werden, wie stark das mechanische Strukturieren die Leistung der Lithium-Ionen-Elektroden verbessert.
Dazu wird die gesamte Prozesskette der Produktion von Lithium-Ionen-Batterien an der Produktionslinie des iwbs
durchlaufen. Entlang der Prozesskette stehen zahlreiche Analyse- und Charakterisierungsmethoden, wie z. B. Laser-Scanning-Mikrokopie (LSM), Rasterelektronenmikroskopie, Oszillations-
rheologie und Laserdiffraktometrie, zur Verfügung. Die gefertigten Elektroden werden zu Knopfzellen oder großformatigen Pouch-Zellen verbaut und elektrochemisch charakterisiert. Dabei kommen unterschiedliche Methoden, wie Laderatentests, Spannungsrelaxation oder Elektrochemische Impedanzspektroskopie sowie post-mortem-Ana-
lysen zum Einsatz.
Anforderungen
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Interesse am Herstellungsprozess von Batterien, Erfahrung in Datenauswertung (z. B. Python), eigenständige &
strukturierte Arbeitsweise, Engagement und Zuverlässigkeit, zuverlässiges Arbeiten im Labor.
Kontakt
M. Sc. Josef Keilhofer
Themengruppe Batterieproduktion
Tel.: 089 / 289 55464
Josef.Keilhofer@iwb.tum.de
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KTA |
Masterarbeit: Optische Charakterisierung chiraler Perowskite |
Iglev |
- Research group
- Laser and X-Ray Physics
- Description
Perowskite bilden eine Materialklasse, die in den letzten Jahren aufgrund ihrer herausragenden optoelektronischen Eigenschaften große Aufmerksamkeit gefunden hat. In einer Kooperation mit der Arbeitsgruppe von Prof. F. Deschler (U Heidelberg) untersuchen wir Chiralitätseffekte in geeigneten Perowskiten. In dieser überwiegend experimentellen Arbeit werden verschiedene Formen optischer Spektroskopie eingesetzt. Hierzu werden bereits etablierte Laseraufbauten im Rahmen der Arbeit weiterentwickelt. Insbesondere soll hier SHG-CD-Spektroskopie, (zeitaufgelöste) PL-Spektroskopie und ggf. zeitaufgelöste vis- und mIR-Spektroskopie genutzt werden.
Kenntnisse in Halbleiter- und Materialphysik oder nichtlinearer Optik sind vorteilhaft, aber nicht zwingend. Gleichermaßen kann Erfahrung in der Spektroskopie oder in der Nutzung von Lasersystemen eingebracht werden.
Für weitere Informationen kontaktieren Sie bitte Herrn PD Dr. Hristo Iglev (hristo.iglev@tum.de) oder Herrn Matthias Nuber (matthias.nuber@tum.de).
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AEP |
Masterarbeitsthema „Alterungsmechanismen für Li-Ionen Batteriezellen“ |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
Masterarbeitsthema „Alterungsmechanismen für Li-Ionen Batteriezellen“ - Untersuchung von Alterungsmechanismen einer Li-Ionen Batteriezelle mit Fokus auf das Gasungs- und Swellingverhalten in Abhängigkeit des Zellformates und „State-of-the-Art-Chemie“ -Weiterentwicklung des Test-Setups -Betreuung der durchzuführenden Tests -Analyse der Testdaten -Bewertung der Auswirkungen für die Anwendung in der Elektromobilität -Start ab 01.06.2022 oder nach Rücksprache Kontakt: i. A. Bianca Paulitsch (bianca.paulitsch@evafahrzeugtechnik.de), EVA Fahrzeugtechnik GmbH, München
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KTA |
Messung der Lichtkurve des Crab Nebels (topic is not available any more) |
Greiner |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
- The Crab nebula is the brightest steady gamma-ray source on the sky. As an extended source, it is not expected to change its flux with time. Consequently, it has been used as an inflight-calibration source for basically all high-energy satellites over the last 50 years. In 2011, nature surprised us: the Crab emission faded by 10%. A worldwide campaign set in to observe the Crab at all possible wavelength to understand the cause of the fading. With no clear explanation unraveled, astronomers interest has faded as well.
The present Master thesis shall measure the flux history of the Crab over the last 10 years, using two gamma-ray instruments: Fermi/GBM and INTEGRAL/SPI. This goal splits into two sub-tasks: (1) use our existing software for Fermi/GBM and measure the Crab intensity and spectrum since 2008 - this employes computations on our high-performance computer; (2) expand our existing Python code for GRB analysis of INTEGRAL/SPI towards co-adding day-long exposures, which then can be used to measure the Crab light curve since 2001 (with emphasis on 2011-2021). The goal is to find out, whether the Crab returned to its historical flux state, or continued to fade - thus adding clues to the nature of its variability.
Technically, this thesis involves (i) learning the basics of X-ray/gamma-ray astrophysics, (ii) understanding data analysis of gamma-ray detectors (non-imaging with GBM and coded-mask imaging with SPI), (iii) improving Python programming, (iv) comparing the 2008-2011 results to published results, (v) challenging proposed theories with the lightcurves obtained for 2012-2021. Some background in astrophysics is advantageous, but affinity with Python programming is a must.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
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AEP |
Microwave cryptography with propagating quantum tokens |
Gross |
- Research group
- Technical Physics
- Description
- Quantum cryptography based on continuous-variables is a rapidly growing field of fundamental and applied research. It deals with various topics regarding fundamental limits on data communication & security. In particular, the microwave branch of quantum cryptography demonstrates a large potential for near term applications due to its natural frequency compatibility with the upcoming 5G and future 6G networks. In this context, we plan to investigate microwave photonic states, quantum tokens, which can be used for unconditionally secure storage and transfer of classical information. This security properties are provided by a peculiar combination of the quantum no-cloning theorem and vacuum squeezing phenomenon. The latter effect can be routinely achieved in the microwave regime with superconducting Josephson parametric amplifiers, which we plan to use for experimental generation & investigation of quantum token states.
This master thesis will focus on developing numerical & experimental tools for the ongoing microwave quantum cryptography experiments. This includes programming various elements of FPGA data processing routines, performing cryogenic measurements with propagating microwaves, and analyzing measurement data for quantifying quantum correlations & unconditional security in propagating quantum token states.
- Contact person
- Kirill Fedorov
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AEP |
Modeling of the FRM II core |
Märkisch |
- Research group
- Particle Physics at Low Energies
- Description
- highly enriched uranium (HEU) to lower enriched uranium. This program is part of worldwide efforts to minimize the usage of HEU in research reactors. For this reason, a parameter study is set up in order to identify possible and compatible FRM II core designs for conversion.
The working group “Reactor Physics” at FRM II is actively working on developing new core designs for the conversion of the FRM II. In order to reach the goal of a core with the lowest enrichment possible, a parameter study is set up that aims to identify possible and compatible FRM II core designs. As a first essential step, several 3D Computational Fluid Dynamics (CFD) codes for use in high performance research reactors are available to perform a code-to-code verification based on experimental results.
Within this thesis, the potential of Ansys Fluent for the FRM II core will be explored. You will get familiar with the physics of modelling fluids with the Navier-Stokes equation, the intricacies of the simulation program and the FRM II core. You will develop and verify suitable postprocessing tools and compare results by Fluent and Ansys CFX.
- Contact person
- Christian Reiter
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KTA |
Modellierung relativistischer Elektronen in Tokamak Plasmen |
Günter |
- Research group
- Max-Planck-Institute for Plasmaphysics (IPP)
- Description
-
Major tokamak disruptions are one of the major challenges for realizing a tokamak fusion power plant. During such an event, the energy confinement of the plasma gets lost on a short time scale such that the temperature of the plasma drops by orders of magnitude. As a result of the increasing resistivity and the large plasma current, a strong toroidal electric field arises that can accelerate electrons to relativistic velocities. Via collisions, the number of such runaway electrons (REs) can increase exponentially until the whole plasma current is carried by REs. When such an RE beam is eventually lost in a future reactor like ITER, it could lead to massive loads onto material components and deep melting such that avoidance and mitigation is of high priority. Experiments in present devices provide an excellent basis for developing and validating modeling tools that can eventually predict the phenomena in ITER. One of the puzzling observations from the ASDEX Upgrade experiment in Garching is that the formation of a RE beam depends on the value of the edge the field line helicity close to the plasma boundary ("safety factor" q95). Large scale plasma instabilities are likely playing an important role for this threshold.
The non-linear magneto-hydrodynamic (MHD) code JOREK (see the code website https://www.jorek.eu) developed by an international community has the necessary ingredients to simulate REs in realistic 3D tokamak geometry and their interaction with plasma instabilities. The aim of this master project is to simulate experimental discharges with and without RE beam formation using a RE fluid model to reveal the origin of the experimentally observed threshold. The work will be conducted within the "MHD and fast particles group" at the Max Planck Institute for Plasma Physics in Garching in close contact with the experiment and our international collaborators.
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KM |
Nachweis von Spin-Orbit-Torques mit Hilfe eines stehenden Spinwellenmusters |
Back |
- Research group
- Experimental Physics of Functional Spin Systems
- Description
- Current-induced spin-orbit torques (SOTs) in ferromagnet/nonmagnetic metal heterostructures open vast possibilities to design spintronic devices to store, process, and transmit information in a simple architecture. It is a central task to search for efficient SOT devices, and to quantify the magnitude as well as the symmetry of current-induced spin-orbit magnetic fields (SOFs). Here, we will evaluate an approach to determine the SOFs based on magnetization dynamics by means of time-resolved magneto-optic Kerr microscopy. A microwave current in a narrow Fe/GaAs (001) stripe generates an Oersted field as well as SOFs due to the reduced symmetry at the Fe/GaAs interface, and excites standing spin wave (SSW) modes because of the lateral confinement. Due to their different symmetries, the SOFs and the Oersted field generate distinctly different mode patterns. Thus, it is possible to determine the magnitude of the SOFs from an analysis of the shape of the SSW patterns. Specifically, this method, which is conceptually different from previous approaches based on line shape analysis, is phase independent and self-calibrated. It can be used to measure the current-induced SOFs in other material systems, e.g., ferromagnetic metal/nonmagnetic metal heterostructures.
- Contact person
- Lin Chen
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AEP |
Near-infrared Quantum Dot Solar Cells for Space Application |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
-
We’re looking for a master student to join the next flight project of NIR CQDs solar cells to space. The general idea about this research topic and your major tasks in this project are introduced as follow.
Quantum dots (QDs) are semiconductor nanocrystals with typical size of 2-10 nm. When the size of materials become very small in the range of nanometers, the optoelectronic properties or other properties are significantly different from their bulk counterparts. Notably, colloidal QDs’ unique advantages and properties have shown great promises as the light absorbers in solar cells, such as solution-processability and size tunability of bandgap, which enables the QD absorbers to harvest infrared low-energy photons of the solar spectrum beyond the absorption edge of silicon very efficiently. Therefore, as opposed to the costly and complicated fabrication process of conventional NIR solar cells, colloidal QDs based NIR solar cells have shown great promises. To date, great advances and improvements of the device performance, exceeding efficiencies of 10 % already, have been achieved by several fabrication strategies.
In a previous experiment, we launched organic and perovskite solar cells to space for the first time ever and studied how these devices operate in the space environment. For the second space flight, we want to test the operation of NIR colloidal QD solar cells in orbital altitudes for the first time. Here, your master thesis starts.
The first part of your project will be to learn how to fabricate NIR CQD solar cells and characterize them with different spectroscopic and morphologic analysis methods. You will find yourself in a team of motivated master students that are all working on the fabrication and optimization of their solar cell systems, where knowledge exchange and communication create a solid base for a productive and educational environment. Thus, you will learn a lot about solar cells and the principles behind many of their typical characterization methods. Based on your measurements of your solar cells, you will be guided to optimize the fabrication methods and solar cell layers to improve the device performance.
The second part of this project will be to study your solar cells before and after their space flight to learn how the solar cells behave after experiencing extreme conditions during the rocket flight and exotic space environment. Your novel results will be worth publishing in a scientific journal, giving you the possibility to become a co-author in this future work. We’re looking forward to meeting you and telling you more about this project!
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KM |
Neuronale Netzwerke zur Berechnung von Ramanspektren |
Egger |
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KTA |
Nichtlineare MHD-Simulationen zum X-Punkt-Strahler in Tokamaks |
Günter |
- Research group
- Max-Planck-Institute for Plasmaphysics (IPP)
- Description
- One of the most important challenges in magnetic fusion research is the heat exhaust at the plasma edge. Without any additional measures, the heat fluxes at the edge of a fusion power plant would be similar to the heat flux at the surface of our sun. The usual solution for that problem is to modify the magnetic field geometry in such a way that the last closed flux surface (separatrix) leads the heat flux along magnetic field lines into a so-called divertor chamber where high plasma densities and low temperatures ensure high radiation losses, protecting the metallic walls of the device. A quite new development in this respect is to create a zone of high radiation within the last closed flux surface just above the so-called X-point by injecting dedicated impurities into the plasma. These impurities result in strong radiation losses that might cause pressure gradients within a magnetic surface. The latter corresponds to an MHD unstable situation. The task of this master thesis is to model such situations, using our non-linear MHD code JOREK, in order to understand and optimize heat exhaust by X-point radiation.
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AEP |
Novel nanostructured thermoelectric hybrid materials |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- In this project, we aim to fabricate and investigate novel organic-inorganic hybrid materials for thermoelectric applications. The goal is to realize efficient low temperature (T < 100°C) thermoelectric thin films and coatings which can contribute for example to energy efficient buildings. By combining nanostructured inorganic materials with conducting polymers a novel approach for this class of materials shall be realized. Possible inorganic nanomaterial components include Silicon nanocrystals (either undoped, n-type or p-type doped) as well as other nanoparticles. Different polymer materials such as the polymer blends of conjugated polymers, which can be tuned in conductivity and in its nanostructure, shall be used as the organic partner in our hybrid approach.
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AEP |
Observation of quantum switching in driven-dissipative superconducting oscillators |
Gross |
- Research group
- Technical Physics
- Description
- Classical nonlinear systems are known to exhibit metastable behaviour, where spontaneous transitions may take place. These transitions are often associated with spontaneous symmetry breaking and can be viewed as classical phase transitions. However, recent developments in quantum theory of driven-dissipative nonlinear resonators reveal that the underlying switching processes may be of purely quantum nature. This can be experimentally observed during the transient dynamics in nonlinear superconducting resonators. An immediate goal of this master project is to experimentally study switching dynamics in driven Josephson parametric amplifiers (JPAs) and observe quantum features, such as vacuum squeezing and Wigner function negativity, in the associated transient resonator states. The far-reaching goals of this research are related to fundamental investigation of quantum phase transitions in novel driven-dissipative superconducting systems, such as quantum metamaterials.
In the framework of this project, the student will experimentally employ existing JPA devices as both the driven-dissipative system and quantum preamplifiers. The latter will be the key for efficient observation and quantum tomography of the transient JPA dynamics. More specifically, the tasks of the master student will consist of the FPGA programming, construction of an experimental set-up in a dilution refrigerator, cryogenic microwave measurements, and data analysis in collaboration with external theory partners.
This project will be an important integral part of our various activities on quantum microwave communication, where JPAs are employed as the key building blocks. These activities are supported within the framework of the MCQST cluster, QMiCS project (EU Quantum Flagship), QuaMToMe project (BMBF, "Grand Challenge der Quantenkommunikation"), and will also have a significant overlap with the QuaRaTe project (BMBF) on quantum sensing.
- Contact person
- Kirill Fedorov
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AEP |
Optomechanics of coupled micro-drums |
Poot |
- Research group
- Quantum Technologies
- Description
- In this project you will dive into the interesting field of cavity optomechanics. We create micrometer-scale mechanical devices made from silicon nitride using advanced nanofabrication techniques here on campus: imagine a drum, but now more than 10 000x smaller! So small that it can be played ustilizing the momentum of photons, the so-called radiation pressure. You will also use light to extract information about mechanical properies - like their quality factors and resonance frequencies and even see their eigenmodes. What happens to these properties when many of the drums are coupled? That will be the key question of your project.
We apply a novel technique to perform usually very long measurements on rather short time scales. We already have some working samples, so you can directly start and go ahead with the measurements. But you will also have the chance to learn many aspects of nanofabrication and make your own devices in the cleanroom, then measure them, and analyze the data.
- Contact person
- Menno Poot
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AEP |
Perovskite Solar Cells for Space Applications |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Perovskite solar cells have become a hot research topic in the last few years. The lightweight thin-film solar cells are of particular interest for space applications due to their exceptional power per mass, exceeding their inorganic counterparts by magnitudes. Recently, we performed the Organic and Hybrid Solar Cells In Space experiment (OHSCIS) and launched of perovskite solar cells to space for the first time. The mechanical and electronic design of the experiment aimed at maximizing the data collection rate and precise measurements. We showed that the perovskite solar cells operate in space conditions and produce reasonable power per area of up to 14 mW cm-2. Also during a phase being turned away from the sun, the solar cells produced power from collecting faint Sun-light scattered from Earth. Our results highlight the potential for near-Earth applications and deep space missions of these technologies.
Soon a next space missing will come up and presently we are looking for an interested master student to join the exiting next flight of perovskite solar cells to space. The task will be to make new sets of perovskite solar cells and test them with the set-up. After the successful flight to space, the solar cell data need to be evaluated and analyzed in detail to learn from the space flight.
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KTA |
Populationsanalyse von kurzen GRBs und Super-Ausbruechen von Magnetaren (topic is not available any more) |
Greiner |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
- Giant flares are known from very exceptional cases in our Galaxy and the Magellanic Clouds. When such flares are observed from outside the Galactic plane, they are indistinguishable from short GRBs. The population analysis aims at identifying the fraction of short GRBs which could be mis-identified as magnetars in bright nearby galaxies.
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AEP |
Printed polymer-based thin film batteries |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
-
Materials for high energy density, solid-state batteries have been tremendously explored in the last decade. In particular, lithium-ion technology has attracted major interest. Among the many different types of batteries, the so-called polymer-based thin film batteries are very attractive as they can be incorporated into thin film devices. An inherent important part of such thin film lithium ion batteries is the membrane and solid-state polymer electrolyte membranes have attracted high attention in this respect. Lithium ions’ incorporation into solid-state polymer electrolyte membranes had shown a significant effect on both, the structure and properties, of the membranes in either the bulk or film format. The morphological reorganization and the thermodynamic properties of the solid-state polymer electrolyte membrane upon adding lithium salts and small molecules are the subjects of the experimental investigation. The polymer membranes will be prepared with printing. The structure and crystallinity of the lithium-doped membranes at different temperatures will be investigated with small/wide-angle X-ray scattering (SAXS/WAXS). The effects of morphology on the ionic conductivity of these ion-conducting membranes will be investigated using impedance spectroscopy. Aim of the present study is to increase conductivity with the help of small molecule additives, which can further improve the membrane morphology beyond the possibilities of the standard approach. Such high conductivity will be very beneficial for further downsizing of polymer-based thin film batteries.
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AEP |
Radioluminescence microscopy for organoid specimens |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Radioluminescence microscopy (RLM) is a novel approach for high-resolution imaging of the radionuclide uptake in living cells, particularly in organoid systems. This project will focus on the development of an experimental setup, which allows imaging the radionuclide distribution with a few micro-meter resolution, using a scintillator-lens CCD system. This project will be carried out in collaboration with the department of nuclear medicine at the TUM university hospital Klinikum rechts der Isar.
Character of thesis work: experimental (50%) / computational (50%)
For more information, please contact: Martin Dierolf (martin.dierolf@tum.de), Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Martin Dierolf
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AEP |
Real-Time DEMS Investigation of Catalytic Processes |
Schindler |
- Research group
- Chemical Physics Beyond Equilibrium
- Description
- Aim of this research project is a better understanding of the complexity of catalytic processes at respective electrode surfaces. This is of great importance, e.g., in fuel cell research and development as well as in CO2 reduction processes. The proposed project is intended to provide a much better correlation of the electrode potential and specifity of the electrode surface with reaction products, and the interference of competing electrochemical processes with each other at the same electrode potentials.
DEMS is an abbreviation for Differential Electrochemical Mass Spectroscopy. This technique allows for the detection of reaction products in situ and in operando with a resolution of less than 10-15 mol/s.
- Contact person
- Werner Schindler
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AEP |
Remote entanglement of superconducting qubits |
Gross |
- Research group
- Technical Physics
- Description
- Quantum computing represents a promising information processing paradigm exploiting quantum properties, such as superposition and entanglement. The latter entity is crucial for achieving quantum advantage in scalable quantum information processing with distributed quantum computers, including those built with superconducting qubits. Here, an important task is to study how quantum entanglement can be distributed between remote superconducting qubits. To this end, we plan to exploit propagating two-mode squeezed states as a carrier of quantum entanglement. We intend to analyze their interactions with remote superconducting quantum bits in theory & verify our findings in experiments.
This master thesis will first focus on theory & numerical simulations of remote entanglement of superconducting qubits with propagating squeezed light. Later project stages may also include cryogenic experiments with superconducting transmon qubits & Josephson parametric amplifiers towards verifying novel concepts of remote entanglement.
- Contact person
- Kirill Fedorov
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KTA |
Sampling anharmonic phonons in energy materials |
Egger |
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KM |
Selective breakdown of phonon quasiparticle picture in halide perovskites |
Egger |
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KM |
Semiconductor photoanodes for photoelectrochemical water splitting |
Sharp |
- Research group
- Experimental Semiconductor Physics
- Description
- The Chair for Experimental Semiconductor Physics (Prof. Sharp) at the Walter Schottky Institute of the Technical University Munich (TUM) investigates novel photoelectrode materials for solar energy conversion applications. Our research also explores new materials and different design strategies to improve the photoelectrochemical (PEC) activity and stability of energy materials under operation conditions. More information can be found on our website www.wsi.tum.de. The Master’s project will focus on photoelectrochemical water splitting to generate hydrogen as storable chemical fuel using multi-layer semiconductor photoelectrodes.
In this context, one of the main challenges is the material stability under the harsh PEC operating conditions. To overcome this limitation, the Master’s project will focus on protecting/passivating the semiconductor surface with conformal functional layers. Specifically, you will synthesize cobalt oxide thin films by plasma-enhanced atomic layer deposition on semiconductor light absorbers to yield stable and catalytically active photoelectrodes. Thereby you will explore the influence of composition, optical and interface properties on the photoelectrochemical characteristics. Furthermore, you will investigate these multilayer photoelectrodes under operando conditions utilizing nanoscale microscopy and spectroscopy techniques to gain fundamental insight into their performance under oxygen evolution condition.
In our group, you will have the chance to gain hands-on experience in atomic layer deposition of thin catalyst layers, state-of-the-art spectroscopy and microscopy techniques, optoelectronic and diffraction techniques, as well as detailed understanding of the physics of functional semiconductors. Dedicated support from a PhD student will be available during your project.
Applications should be send to johanna.eichhorn@wsi.tum.de. Please include your CV, a copy of your BSc thesis, and the transcript of records (Bachelor & Master)
- Contact person
- Johanna Eichhorn
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KTA |
Sensitivity study of a distributed network of neutrino telescopes: MonteCarlo studies, likelihood analysis, and machine learning applied to high energy astrophysics. |
Resconi |
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AEP |
Silicon-Germanium based anode coatings for Lithium-ion batteries |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Lithium-ion batteries (LIBs) have taken over a major role in the field of energy storage since several years. Especially in sectors such as portable devices, renewable storage systems and electric vehicles, this technology is already dominating the market. In order to meet the ever-increasing requirements such as durability, energy density and manufacturing costs, it is essential to implement new performance-enhancing materials into the cell architecture. Group IV elements as Silicon (Si) and Germanium (Ge) are considered to be appealing alternatives to commercial graphite anodes due to their high-energy capacity. In this respect, Si is becoming the focus of research due to the highest theoretical capacity (4200 mAh g-1) and low working potential. Additional advantages such as environmental friendliness, resource abundance and low cost have prompted several research groups around the world to look closer into this topic. However, the cycling performance and the rate capacity of these novel anodes are still limited by the low intrinsic electron conductivity and poor Li+ diffusivity. In addition, Ge can provide better cyclability and a dramatically improved electron conductivity into the system. Within this thesis, we focus on diblock copolymer templating of Si/Ge thin films as novel anode materials for LIBs. Here CR2032 Litihium-ion coin cells will be manufactured. Mayor topic will be an extensive study on different anode coatings with real and reciprocal space analysis methods.
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BIO |
Simulating the collective motion of encapsulated enzymes in external substrate gradients |
Gerland |
- Research group
- Theory of Complex Bio-Systems
- Description
- Recent experiments revealed that the diffusion coefficients of enzymes can depend on the concentration of their corresponding substrates: the enzyme diffuses faster in the presence of more substrate. The aim of this thesis is to understand the consequences of this effect on the collective motion of enzymes. Imagine a vesicle immersed in a substrate gradient and loaded with thousands of units of a specific enzyme. What would happen to this vesicle? Would the non-uniform motion of the enzymes inside affect the shape of the vesicle? And what kind of deformations could be produced? Would it be possible to cause the movement of the vesicle along a preferred direction? To tackle these questions, you will be involved in the implementation of Brownian dynamics simulations combining a mesh description of the vesicle, the diffusion-dependent movement of enzymes and the interactions between the enzymes and the vesicle. With this work you can contribute to some of the latest developments in enzyme dynamics and active matter. Moreover, your results can be utilized to design and analyze experiments. Prerequisites: Interest in biophysical systems and in simulations of dynamical systems.
- Contact person
- Giovanni Giunta
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KTA |
Simulation vertikaler Plasmainstabilitäten am ASDEX Upgrade Tokamak |
Günter |
- Research group
- Max-Planck-Institute for Plasmaphysics (IPP)
- Description
- Fusion plasmas with a vertically elongated cross section like they are studied in present tokamaks and are foreseen for the large future ITER experiment develop vertical instabilities when the energy confinement of the plasma is lost during the “thermal quench” of a major disruption event. Non-linear magneto-hydrodynamic simulations coupled to resistive wall models describing the conducting structures (such as vaccum vessel and coils) can reproduce experimentally observed phenomena accurately. For ITER, vertical instabilities are a big concern as they can, e.g., lead to large forces onto conducting structures as well as massive heat loads onto plasma facing components. Beyond a threshold of the plasma elongation, the vertical instabilities can normally not be avoided even with active control. There is, however, an experimental observation from ASDEX Upgrade that the plasma may remain vertically stable in spite of significant elongation under specific conditions. Theoretically, such a “neutral point” for the vertical motion is expected, but it is not clear from experiment and theory how robust it would be.
In this master project, the described experimental condition will be simulated with the non-linear magneto-hydrodynamic (MHD) code JOREK (see the code website https://www.jorek.eu). The aim is to reproduce the neutral point observation and study the robustness to small variations of the plasma configuration (initial current and pressure profile, initial location, etc.). If possible, concrete proposals for future experiments should be deduced that will allow to validate the findings. The work will be conducted within the "MHD and fast particles group" (very international, English speaking) at the Max Planck Institute for Plasma Physics in Garching in close contact with the experiment and our international collaborators.
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AEP |
Smart nano-sensors made of stimuli-responsive polymers in solution and in thin films |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Whereas macroscopic sensors made of stimuli-responsive hydrogels are well established, in the nanoworld such sensors still face many challenges. Potential fields of application of such sensors extend from engineering to bioengineering and medicine, e.g. as nanosensors for the control of concentration of glucose for diabetes patients or as switchable surface in the frame of tissue engineering. In this experimental project smart hydrogels, made of stimuli-responsive hydrogels will be investigated. Hydrogel films with thicknesses of a few tens to some hundreds of nanometers and spontaneously deswell or swell due to external stimuli, like temperature or the concentrations of ions. The changes in thickness and in molecular interactions in swelling or collapsing hydrogels will be probed during the switching process by different lab-based techniques. A comprehensive understanding of the switching process can be achieved by complementary neutron scattering experiments at large scale facilities. The project will involve a literature review, preparation of hydrogels, as well as experimental investigations and interpretations of the repeated switching of the stimuli-responsive hydrogels.
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AEP |
Spectral material decomposition with dual-energy, photon-counting X-ray detectors for industrial applications |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Despite being meanwhile well established and broadly available in medical imaging applications, spectral material decomposition using photon-counting hybrid pixel detectors is presently still underused in industrial imaging tasks. The main goal of this project is therefore to translate the existing theoretical and experimental knowledge from photon-counting biomedical imaging applications to industrial inspection applications. The work includes numerical programming tasks, such as implementing and refining decomposition algorithms, and experimental tasks, such as taking several best practice measurement to classify different material separation applications for industrial end-users.
This master thesis will be carried out in collaboration with an external industrial collaborator located in the Munich area.
Character of thesis work: experimental physics (50%) & image processing (50%)
For more information, please contact: Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Daniel Berthe
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AEP |
Spectral material decomposition with dual-energy, photon-counting X-ray detectors for industrial applications |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Despite being meanwhile well established and broadly available in medical imaging applications, spectral material decomposition using photon-counting hybrid pixel detectors is presently still underused in industrial imaging tasks. The main goal of this project is therefore to translate the existing theoretical and experimental knowledge from photon-counting biomedical imaging applications to industrial inspection applications. The work includes numerical programming tasks, such as implementing and refining decomposition algorithms, and experimental tasks, such as taking several best practice measurement to classify different material separation applications for industrial end-users.
This master thesis will be carried out in collaboration with an external industrial collaborator located in the Munich area.
Character of thesis work: experimental physics (50%) & image processing (50%)
For more information, please contact: Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Daniel Berthe
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AEP |
Strukturen für den Ursprung des Lebens |
Alim |
- Research group
- Theory of Biological Networks
- Description
Weiße Raucher sind wahrscheinlich die Wiege des Lebens. Ihre Höhlen und Tunnel ermöglichen es Reaktanten an katalytischen Stellen anzusammeln, um damit die Reaktionen am Ursprung des Lebens in Gang setzen. Wie entstehen und wachsen diese katalytischen Stellen mit dem Smoker? Sie werden zweidimensionalen Smoker auf einem Mikrofluidik-Chip wachsen lassen und aus Ihren Daten die Rauchergeometrie vermessen und damit Strömung und Transport im Netzwerk berechnen und mit Ihren Daten vergleichen. Sie lernen Mikrofluidik, Mikroskopie, Matlab, Bildanalyse und die Strömungsphysik der laminaren Strömung in Strömungsnetzen kennen. Voraussetzungen: Statistische Physik und Faszination für die Wunder der Natur.
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BIO |
Studying the bacterial life cycle and morphology using flow cytometry |
Gerland |
- Research group
- Theory of Complex Bio-Systems
- Description
The flow cytometer is an optical device that can measure cell properties at a single cell level with a high throughput. The aim of this Master thesis is to explore the dynamics of bacterial populations using flow cytometry to address the following questions: How does a cell population change at the onset of growth arrest? What are the dynamics of cellular viability during starvation? Do bacteria uniformly die under starvation or are there growing subpopulations? Can one accurately infer morphological information from flow cytometry data? How can cell dynamics under starvation be modeled with the help of stochastic processes?
- Contact person
- Seyed Hamid Seyed Allaei
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KM |
Synchronization and nonlinear dynamics of nanomechanical oscillators |
Poot |
- Research group
- Quantum Technologies
- Description
Synchronization is a universal phenomenon that is knows since they days of Huygens. When two or more oscillators with slightly different frequencies are coupled, they will start to move in phase. We can create small mechanical devices using advanced nanofabrication techniques here on campus. By sending light of the right wavelength, they start to oscillate, and when increasing the power the optomechanical coupling synchronizes them. The goal of this project is to synchronize devices made from silicon nitride, which is a special material with a lot of stress in it, and to increase the number of synchronized oscillators. The larger the system becomes, the richer the nonlinear dynamics will become. You will first make the devices in the cleanroom, measure them, and analyze the data.
See http://www.groups.ph.tum.de/en/qtech/openings/ for a detailed description of this project.
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AEP |
Theoretical investigations of dynamic effects in bismuth vanadate |
Egger |
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KTA |
Toward a complete b->u l nu fit in the Weak Effective Theory |
van Dyk |
- Research group
- Theoretical Elementary Particle Physics
- Description
You will use the EOS software to generate a hypothetical data set of experimental measurements, and use it to validate a fit of the b->u l nu Wilson coefficients of the effective theory. You will take care to explore possible blind directions in the parameter space, and seek new observables that break these blind directions. Your thesis will pave the way toward a complete extraction of the experimental information contained in upcoming data sets by the LHCb and Belle II experiments.
Knowledge of Python is required.
- Contact person
- Meril Reboud
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AEP |
Two-dimensional Pattern Formation via Local Cell-Cell Signaling |
Gerland |
- Research group
- Theory of Complex Bio-Systems
- Description
- Pattern formation phenomena occur in many different contexts ranging from physical and chemical systems to developmental biology and synthetic biology. For instance, in developmental biology, the correct relative positioning and determination of different cell fates is essential to ensure that the organism functions correctly. Whilst many models for pattern formation have been studied, the focus here is on cellular systems with interactions only between neighboring cells. This form of communication has previously received less attention from theoretical research than e.g. long-range diffusible signals as a means of communication. Our goal is to explore fundamental limits, patterning concepts, and engineering potential with a simple top-down model. Building on previous work, the project will concentrate on searching mechanisms of pattern formation with the goal of investigating which information processing and communication logics can robustly produce different prototypical patterns in two spatial dimensions. Prior knowledge in biology/biophysics is not needed, but interest in theoretical physics and computational problem solving is expected.
- Contact person
- Stephan Kremser
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KTA |
Untersuchung der Signalantwort des MADMAX Experiments zur Suche nach Axionen als dunkler Materie |
Majorovits |
- Research group
- Max-Planck-Institute for Physics / Werner-Heisenberg-Institute (MPP)
- Description
Im Rahmen des MADMAX Projektes zur Suche nach dunkler Materie Axionen werden verschiedene Testaufbauten bei Raumtemperatur und in flüssigem Helium (4 K) zur Kalibrierung und zur Untersuchung der genauen Signalantwort des experimentellen Aufbaus betrieben. Es werden Reflektionsdaten Daten genommen und ausgewertet.
In the frame work of the MADMAX projects several test stands at room tamperature and in liquid helium for the investigation of the detailled system response and for calibration of the setup are being operated. Reflectivity data will be atken and analyzed.
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KTA |
Untersuchung und Verbesserung des Verhaltens von sMDT-Kammern bei hohen Gammastrahlungsuntergrundraten |
Kroha |
- Research group
- Max-Planck-Institute for Physics / Werner-Heisenberg-Institute (MPP)
- Description
- Das Verhalten neuer Myondetektoren (small-diameter Muon Drift Tube Detektoren, sMDT-Kammern) fuer kuenftige Experimente an hochenergetischen Teilchencollidern soll unter den diesen Experimenten zu erwartenden extrem hohen Untergrundstrahlungssraten untersucht werden. Dazu werden Daten in einem Myonstrahl in der Gamma-Bestrahlungseinrichtung am CERN aufgenommen und analysiert. Das Schwergewicht der Arbeit liegt an der Auswertung der Daten. Ein Aufenthalt am CERN zum Aufbau des Experiments und zur Aufnahme der Daten kann in Betracht gezogen werden.
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BIO |
Vasculature remodeling following a ‘stroke’ |
Alim |
- Research group
- Theory of Biological Networks
- Description
- Our vasculature forms redundant connections to robustly provide supply via the stream pervading our vasculature. Yet, vessel occlusions, strokes, threaten the steady supply by interrupting transport. Which network geometry poses a vasculature at risk in the event of a stroke? You will quantify network dynamics in existing data of both or network model organism Physarum polycephalum and human vasculature culture on a chip. Mathematically estimating the importance of individual veins within observed networks will guide you to identify which network geometries pose risks. You will learn about fluid flows in networks, Matlab. Prerequisites: Electrodynamics
Task 1 Learn how to calculate resistances and network equivalent resistances in flow networks
Task 2 Quantify vein resistances in different experimental data of vasculature. Preliminary code is provided.
Task 3 Compare your predictions to real data of vasculature remodelling. Built a hypothesis which network geometries are at risk. Calculations of network resistances on small model networks may help you here.
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KM |
Zeitaufgelöste Messung des Umschaltprozesses für in der Ebene magnetisierte mikrostrukturierte Elemente |
Back |
- Research group
- Experimental Physics of Functional Spin Systems
- Description
- The demonstration of magnetization switching induced by spin-orbit torques in a ferromagnetic metal (FM)/heavy metal (HM) bilayer has attracted tremendous attention due to possible application in magnetic random access memories (MRAM). Typically, an in-plane current sent through the heavy metal layer (e.g. Pt) gives rise to a spin accumulation at the FM/HM interface due to the spin Hall effect. The spin accumulation acts on the ferromagnet (e.g. Co) via the spin transfer torque effect and leads to magnetization dynamics and, ideally, to switching.
In this Master thesis, we will use time resolved magneto-optical Kerr microscopy (TRMOKE), which is a time and spatially resolved technique, to trace the switching dynamics of an in-plane magnetized ferromagnetic metal. The following points will be addressed:
1) The Co/Pt thin films will be patterned to micrometer-size devices by using a by mask-free laser writer or by electron-beam lithography.
2) Time and spatially resolved magnetization dynamics will be measured by TRMOKE.
3) Finally, the experimental data will be compared to theory.
- Contact person
- Lin Chen
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