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KTA |
Absorption of antinuclei in ALICE Time Projection Chamber using machine learning algorithms |
Fabbietti |
- Research group
- Dense and Strange Hadronic Matter
- Description
Dark Matter (DM) is believed to account for roughly 27% of the mass-energy of our Universe, and its nature remains one of the most intriguing unsolved questions of modern physics. Multiple balloon- and space-borne experiments are searching for the traces of DM using the idea of possible annihilation or decay of DM particles into ordinary (anti)particles, including light (anti)nuclei. The latter (such as antideuterons and antihelium nuclei) are considered as especially promising probe for such indirect DM searches, as the background stemming from ordinary collisions between cosmic rays and the interstellar medium is expected to be very low with respect to the DM signal. In order to reliably estimate the fluxes of antinuclei near Earth stemming from DM and from background, it is necessary to know the probability for antinuclei to interact inelastically with ordinary matter on their way to the detectors (e.g. with interstellar medium and Earth's atmosphere). This probability is driven by the inelastic cross section of corresponding processes, which for antinuclei are still poorly (or not) known. This fact hinders precise calculations of antinuclei fluxes near Earth and forces existing estimates to rely on extrapolations and modelling. The here advertised master project will deal with the analysis of inelastic interactions of antinuclei inside the gas volume of the Time Projection Chamber of the ALICE detector. Such interactions typically create a bunch of secondary (charged) particles with low momentum with a characteristic topology of secondary vertex inside the TPC volume. The pattern can be recognised by machine learning algorithms trained on simulated events, in which such annihilation processes happen in a controlled environment. After the validation of algorithms with simulated events, one can analyse real experimental data and tag the annihilation events of interest, which in turn can be used to evaluate the effective antinuclei + A inelastic cross section. This project will be structured in the following way: - simulation of the inelastic interactions of antinuclei with the TPC gas using Geant4 toolkit - training and validation of neural networks to reliably recognise antinuclei annihilation events - Analysis of the ALICE experimental data from pp collisions at sqrt(s) = 13 TeV - Evaluation of the effective antinuclei + A inelastic cross sections - Contact person
- Chiara Pinto
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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 |
AI in Physics: Convolutional neural networks for dark-field X-ray CT reconstruction |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Grating-based X-ray dark-field 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: mainly computational physics & image processing
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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AEP |
A satellite for sodium spectroscopy in the mesosphere |
Fierlinger |
- Research group
- Precision Measurements at Extreme Conditions
- Description
- We are looking for a master thesis student to build the science module for a pico-satellite at a 450 km orbit, to map the magnetic field of the earth at 92 km altitude in the mesosphere through laser spectroscopy of sodium atoms.
Large telescopes use laser beams at the sodium wavelength pointing into the sky to generate a bright dot, an artificial star, in the mesosphere through fluorescence of sodium atoms. This dot is used to correct for atmospheric fluctuations to improve imaging.
Our project uses this knowledge, but for a different purpose: we mount the laser on a satellite and point downwards to the earth. When the light hits the mesosphere, a bright spot is generated. If the light is modulated at the electron spin resonance frequency corresponding to the magnitude of the earth field, this is a direct measure of the magnitude of the earth’s magnetic field.
The thesis work will be the test of the laser system in the lab, generating fluorescence, detecting the fluorescent light with a silicon photomultiplier and prepare components for a space exposure test at the international space station. Here you will learn atomic and particle physics techniques and applications. If you always wanted to build your own satellite and learn how satellite technology works, contact Florian Kuchler (florian.kuchler@tum.de)
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KM |
Aufbau eines Dreifach-Kühlfingers zur Gammaspektroskopie mittels hochreiner Germaniumdetektoren |
Hugenschmidt |
- Research group
- Neutron Scattering
- Description
- Hochreine Germaniumdetektoren werden bei Flüssigstickstofftemperatur betrieben, um die für Gammaspektroskopie benötigte extrem hohe Energieauflösung zu erreichen. Im Rahmen dieser Arbeit soll ein Dreifach-Kühlfinger konstruiert, aufgebaut und hinsichtlich seiner Kühleigenschaften charakterisiert werden. Hierbei soll das Augenmerk auf Temperaturgradienten, Kühl- und Standzeiten gelegt werden, um schließlich einen Dreier-Cluster von Germaniumdetektoren effizient kühlen zu können. Zunächst sollen hierzu Simulationen zur Temperaturverteilung durchgeführt werden, die am schließlich realisierten Aufbau über Messungen verifiziert werden sollen. Schließlich soll die Energieauflösung der Detektoren anhand von aufgenommenen Gammaspektren an einer Referenzprobe gemessen werden.
Das Projekt wird in der TUM Forschungsgruppe Physik mit Positronen durchgeführt.
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KM |
Berechnung der Elektron-Positron-Impulsverteilung an Gitterfehlern (ABINIT) |
Hugenschmidt |
- Research group
- Neutron Scattering
- Description
The characterization of lattice defects with respect to their chemical environment is of outmost interest in condensed matter physics and materials science. In coincidence Doppler-broadening spectroscopy (CDBS), both annihilation quanta are detected simultaneously with two high-purity germanium detectors. The resulting background suppression enables the detection of large momenta of core electrons (large Doppler-shifts) in the outer wings of the 511 keV annihilation line. Therefore, CDBS is applied to identify the elements at the annihilation site and hence enables the detection of, e.g., foreign atom-vacancy complexes or precipitates in alloys. Within this thesis CDBS spectra resulting from positron annihilation in point defects will be calculated by using the open-source code ABINIT. This program is based on density functional theory (DFT) and allows the computation of electron and positron densities as well as wave functions in the solid. The calculated positron lifetimes and positron-electron momentum distributions are compared with experimental results.
The project is carried out within the TUM research group Physics with Positrons.
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KTA |
Building up an electrostatic particle storage ring for fundamental research |
Fierlinger |
- Research group
- Precision Measurements at Extreme Conditions
- Description
- At our lab we are currently building an electrostatic particle storage ring, initially for a dark matter search (https://arxiv.org/pdf/2211.08439.pdf). During this year, we are setting up the hardware for the first stage: a 30 kV barium ion source and the whole experimental hardware of the ring with 2 m side length, here in the lab at our chair in Garching. This includes a vacuum system, electrodes for keeping particles on their trajectories and means for monitoring the particle beam. To perform a dark matter search, we polarize the Ba+ with lasers and lock the electron spin precession to the cyclotron frequency of the beam, effectively forming a crazy magnetic field sensor. Dark matter or other exotic physics would modulate the precession, and we can observe this via laser spectroscopy.
If you are interested in this project, it’s a great time to join the project: all parts are coming in right now, and there is a lot of different physics to learn and work on. During the course of the thesis, the experiment should be assembled and tested with first particles in the ring. Depending on the interests, the work can be more focused on practical aspects or simulations of the details of the ring.
Please contact Chiara Brandenstein (chiara.brandenstein@tum.de) if you are interested!
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KM |
Computational fast screening of core-shell nanoparticles for oxygen reduction reaction in fuel cells |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
Electrocatalysis technologies, including PEM fuel cells, can help to shape a sustainable energy future in which PEM fuel cells provide versatile stationary and portable power solutions. However, one key factor limiting their widespread commercialization are high costs for large platinum (Pt) loadings, which are required to catalyze the sluggish oxygen reduction reaction (ORR) at the fuel cell cathode. Thus, enhancing the catalyst activity with respect to the Pt mass is of great interest.
In this MSc work, we capitalize on data-driven design to propose new Pt catalysts with enhanced mass activities toward the ORR. We link experimental data with results from density functional theory (DFT) on Pt-based ORR catalysts to build a computational model which predicts mass activities.
The thesis will focus on generalizing a developed method based on generalized coordination numbers for high-throughput screenings to tailor electrocatalyst shapes and sizes toward optimized mass activities. In particular, we want to explore core-shell nanoparticles. In core-shell nanoparticles, the catalysis is driven on active Pt shells, but cheaper and more abundant metals at the core limit the precious Pt loading.
Contact: Prof. Alessio Gagliardi alessio.gagliardi@tum.de or Prof. Aliaksandr Bandarenka bandarenka@ph.tum.de
References
[1] M. Rueck, A. Bandarenka, F. Calle-Vallejo, A. Gagliardi, “Oxygen Reduction Reaction: Rapid Prediction of Mass Activity of Unstrained Nanostructured Platinum Electrocatalysts,” J. Phys. Chem. Lett., 2018, 9 (15), 4463-4468. DOI:10.1021/acs.jpclett.8b01864.
[2] B. Garlyyev(1), K. Kratzl(1), M. R¨uck(1), J. Michalicka, J. Fichtner, J. Macak, T. Kratky, S. Guenther, M. Cokoja, A.S. Bandarenka, A. Gagliardi, R.A. Fischer, “Optimizing the Size of Platinum Nanoparticles for Enhanced Oxygen Electro-Reduction Mass Activity,” Angew. Chem. Int. Ed., 2019, 58 (28), 9596-9600. DOI:10.1002/anie.201904492
[3] M. Rueck, A. Bandarenka, F. Calle-Vallejo, A. Gagliardi, “Fast Identification of Optimal Pure Platinum Nanoparticle Shapes and Sizes for Efficient Oxygen Electroreduction,” Nanoscale Adv., 2019, 1 (8), 2901–2909. DOI:10.1039/c9na00252a
[4] M. Rueck, B. Garlyyev, F. Mayr, A.S. Bandarenka, A. Gagliardi, “Oxygen Reduction Activities of Strained Platinum Core–Shell Electrocatalysts Predicted by Machine Learning,” J. Phys. Chem. Lett., 2020, 11 (5), 1773-1780. DOI:10.1021/acs.jpclett.0c00214 - Contact person
- Aliaksandr Bandarenka
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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 Wednesday, 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 |
Dark-field Chest X-ray Imaging: Advanced image processing for clinical applications |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Dark-field radiography exploits the scattering of X-rays to visualize structures below the resolution limit. Currently, several initial clinical patient studies are underway on a worldwide first prototype we recently realized at Klinikum rechts der Isar. Within the framework of this project, the special algorithms for image post-processing of these first clinical data will be further optimized and used together with the participating radiologists for the evaluation of better direction of lung diseases.
Character of thesis work: mainly computational physics & image processing
For more information, please contact: Rafael Schick (rafael.schick@tum.de) or Franz Pfeiffer (franz.pfeiffer@tum.de). - Contact person
- Rafael Christian Schick
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AEP |
Dark-field Chest X-ray Imaging: Development of registration algorithms for the analysis of functional lung images |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Dark-field radiography exploits the scattering of X-rays to reveal structures in lung tissue that cannot be visualized with conventional imaging. Currently, several initial clinical patient studies are underway on a worldwide first prototype we recently realized at Klinikum rechts der Isar. Within the scope of this project, special registration algorithms are to be developed that can register thorax images in inhalation and exhalation and allow local differences between ventilation states (for example in certain lung diseases).
Character of thesis work: mainly computational physics & image processing
For more information, please contact: Rafael Schick (rafael.schick@tum.de) or Franz Pfeiffer (franz.pfeiffer@tum.de). - Contact person
- Rafael Christian Schick
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AEP |
Dark-field Chest X-ray Imaging: Monte Carlo based simulation of Compton scattering |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Dark-field radiography is a novel X-ray imaging technique that is being tested for the first time in clinical patient studies on a worldwide first prototype recently completed by us at the TUM Klinikum rechts der Isar. Within the scope of this project, Monte Carlo based Compton simulations will be developed, which will allow an exact modelling of the Compton scattering and thus a better correction of the image artifacts.
Character of thesis work: experimental physics (50%) & computational physics (50%).
For more information, please contact: Henriette Bast (henriette.bast@tum.de) or Franz Pfeiffer (franz.pfeiffer@tum.de). - Contact person
- Henriette Bast
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AEP |
Dark-field X-ray microCT: Pre-clinical research on improved lung disease detection |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Dark-field computed tomography uses the wave property of X-rays to provide complementary contrasts in X-ray imaging. In this project, an existing prototype for dark-field CT in mice will be used to explore the use of dark-field contrast in pre-clinical research for improved detection of lung diseases in collaboration with the Helmholtz Center for Health. In addition to experimental work to support the conduct of the preclinical studies, algorithmic research to reduce image noise and dose is planned.
Character of thesis work: experimental medical physics (60%) & image processing (40%).
For more information, please contact: Benedikt Guenther (benedikt.guenther@mytum.de), Simon Zandarco (simon.zandarco@tum.de) or Franz Pfeiffer (franz.pfeiffer@tum.de). - Contact person
- Benedikt Günther
- Simon Zandarco
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KTA |
Dark Photon Search with an Array of Atomic Magnetometers |
Fierlinger |
- Research group
- Precision Measurements at Extreme Conditions
- Description
- Atomic magnetometers use non-linear effects in laser-driven electron-spin-resonance in Alkali atoms. Such sensors can measure Femto-Tesla level magnetic fields and have a variety of applications in fundamental physics as well as in applications, for example remote sensing or medicine.
In this project we will set up an array of atomic magnetometers, record the ambient magnetic field and analyze it for spurious effects. As the availability of robust and reliable sensors at this quality is rather new, a yet unexplored parameter region for new physics can be investigated in this way. We are in particular interested in ultra-light axion-like dark matter and dark photons. To be sensitive for such this type of new physics, sensors ultimately need to be placed at a remote and electromagnetically silent location. While some of the sensors are already operational, the experimental work will contain reliable operation of several sensors, as well as developing a mechanism to relate the individual channels e.g. by applying artificial reference signals.
In contrast to laboratory experiments with individual sensors, here the interesting aspect is the analysis of an array of sensors placed in the ambient earth magnetic field, with correlations between sensors, directional information and new possibilities for background suppression and signal identification, e.g. using independent component analysis. We expect to find new challenges in the analysis, but also a much larger amount of information. The data will be fun to interpret, as almost everything is magnetic at the Femto-Tesla scale!
Please contact Peter Fierlinger (peter.fierlinger@tum.de) or Florian Kuchler (florian.kuchler@tum.de) if you are interested.
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KTA |
Datenanalyseverfahren für kontrastreiche Imaging auf astrophysikalischen Daten des SPHERE-Instruments, in Imaging und Polarimetrie (topic is not available any more) |
Eisenhauer |
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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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AEP |
Development and Integration of Algorithms for 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 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
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KTA |
Development and Integration of Algorithms for 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 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
- Martin Losekamm
- Peter Hinderberger
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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
- Martin Losekamm
- Peter Hinderberger
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KTA |
Elektron-Magnetspektrometer zur Detektor-Charakterisierung |
Märkisch |
- Research group
- Particle Physics at Low Energies
- Description
- Precision spectroscopy of electrons from neutron decay allows to determine Standard-Model parameters like the CKM quark-mixing matrix element V_ud and to search for physics beyond the Standard Model like scalar and tensor interactions. At the intense neutron source FRM II we currently take the spectrometer PERC into operation.
In order to characterise and optimise the detector systems in the lab, a magnetic spectrometer will serve as a source of (nearly) mono-energetic electrons. Within this project the existing apparatus will be taken into operation and optimised to measure the response of scintillation detectors with a SiPM readout, as well as silicon detector systems.
- Contact person
- Karina Bernert
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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 |
Exploring the properties of Quark-Gluon Plasma with anisotropic flow measurements at the Large Hadron Collider |
Fabbietti |
- Research group
- Dense and Strange Hadronic Matter
- Description
- The matter produced in ultra-relativistic heavy-ion collisions resembles the
Quark-Gluon Plasma (QGP), which is an extreme state of nuclear matter
consisting of deconfined quarks and gluons. Such a state existed in the early
Universe, just a few microseconds after the Big Bang. Its properties can
be experimentally accessed by measuring the azimuthal anisotropies in the
momentum distribution of produced particles in heavy-ion collisions, for
instance, in lead-lead collisions reconstructed with the ALICE experiment
at CERN's Large Hadron Collider (LHC).
Of particular interest in this context is the anisotropic
flow phenomenon,
which is an observable directly sensitive to the properties of QGP. In this
project, we introduce the basics of anisotropic
flow and corresponding analyses techniques, and we guide a student throughout all steps needed for its final measurement, in the large-scale LHC datasets distributed on Grid.
We start a project by briefly introducing a theoretical framework within
which an anisotropic flow phenomenon can be defined and quantified. Next,
we introduce sophisticated multi-particle correlation techniques, which were
developed recently by experimentalists particularly for anisotropic
flow measurements. We go in detail through the practical implementation of multi-
particle correlations, students are expected at this point to perform some
simple analytic calculations, and to learn and perform programming tasks
both in ROOT and AliROOT. ROOT is the object-oriented analysis frame-
work written in C++ programming language, and it is used at the moment as
a default software in high-energy physics by all major collaborations world-
wide, while AliROOT is the more speci c analysis framework developed by
ALICE experiment, and which is based on ROOT.
We wind up the project by letting the student do an independent ani-
sotropic flow analysis with his/her own newly developed code in AliROOT,
utilizing multi-particle correlation techniques, over real heavy-ion collisions
collected by ALICE at LHC, and stored on Grid.
- Contact person
- Ante Bilandzic
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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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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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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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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 |
High efficiency next generation organic solar cells |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- 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 |
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 region-of-interest mode in diffraction computed tomography |
Petry |
- Research group
- Functional Materials
- Description
Implementation of region-of-interest mode
in diffraction computed tomography
Since its development, X-ray tomography became a non-alternative tool for fast and non-destructive characterisation of different objects providing an in-depth resolved information from the interior of materials, devices and living organisms. Besides the overall popularity and the widley use of the method it suffers heavily from contrast limitation issues, which are directly related to the underlying properties of X-ray attenuation. One of the approaches to enhance the sensitivity of the method (at least in the field of solid-state applications) is the utilization of a diffraction-based input signal instead/together with the absorption-based signal information. X-ray diffraction radiography – a scanning technique taking XRD pattern at each scanning position\pixel (and tomography, as its logical continuation) is a relatively new method for sample characterisation, which requires requiring a large amount of diffraction data as input. However, it is capable to provide unique information about the organisation and composition of the studied objects. The size of diffraction data in a XRD-CT dataset is one of the limiting factors for the resolution of the measurement, i.e. for larger samples. A possible solution for this would be a limitation to certain region-of-interest within the objects volume. Thus, the aim of the proposed thesis is the validation of available approaches for reconstruction of XRD-CT data in the region-of-interest mode and its application for non-destructive studies of cylindrical Li-ion batteries.
Common supervision is foreseen with Dr. Anatoliy Senyshyn, diffraction group leader at MLZ. - Contact person
- Anatoliy Senyshyn
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AEP |
In-situ Electrochemical Electron Paramagnetic Resonance (EPR) Spectroscopy for Battery Systems |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
- In this project, EPR spectroscopy will be used in combination with cyclic voltammetry and impedance spectroscopy for the characterization of electrified solid/solid and solid/liquid interfaces. As most issues of the so-called all-solid-state Li-ion batteries originate from the solid electrolyte-lithium interface, the changes of bulk and thin lithium metal anodes will be investigated. Further, within a solid/liquid system, the EPR will be applied to study the hydrogen evolution reaction (HER) mechanism on the Pt and/or Pd electrodes. The detection of paramagnetic intermediates by EPR in the electrolyte or at the surface of the catalyst will help to understand which intermediates are involved in the HER.
The contact person is Dr. Elena Gubanova, e-mail: elena.gubanova@tum.de
- Contact person
- Elena Gubanova
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KM |
Lateral angular momentum transport by phonons |
Gross |
- Research group
- Technical Physics
- Description
- In a solid-state system, spin angular momentum is mediated by various (quasi-)particles. Among these excitations are phonons, which can carry angular momentum over mm distances. Most importantly, exchange of spin angular momentum from these crystal lattice vibrations to excitations of the magnetic lattice is possible via magneto-elastic coupling effects. This unlocks novel means for coherent and incoherent spin transport concepts without moving charges. Your thesis will be dedicated in assessing the realization of incoherent angular momentum transfer in nanostructured systems.
In your thesis you will work on an all-electrical injection and detection scheme to access incoherent angular momentum transfer. You will use state-of-the-art nanofabrication techniques using electron beam lithography and thin film deposition machines for the realization of magnon-phonon hybrid devices. You will also gain experience in cryogenic magnetotransport techniques. You will develop automated evaluation tools and work on modelling the observed phenomena.
- Contact person
- Matthias Althammer
- Hans-Gregor Hübl
- Stephan Geprägs
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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 Wednesday, February 1, 14:00-16:00. For more information please check (here comes an updated link to a moodle). Until then, please send an email to schoenert@ph.tum.de and put your name here https://docs.google.com/document/d/14U-KQA-z-QCrTRaDm6SSNjrUNbmsCv9qe1k6wbGNSus/edit?usp=sharing. Also Bachelor 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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AEP |
Lithium-ion batteries with modified electrolyte for next generation batteries |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Lithium-ion batteries are an indispensable energy supply in modern society. The ideal anode consists of lithium metal due to its high specific energy and low electrochemical potential. However, lithium-ion batteries with liquid electrolyte are prone to form lithium dendrites, which can lead to failure or even explosion of the battery. Therefore, polymer electrolytes are an attractive alternative to bypass these obstacles. However, polymer electrolytes suffer from high contact resistances and low ionic conductivities, which requires an elevated operating temperature. In this project, a hybrid electrolyte based on liquid electrolyte modified with polymer will be prepared. Then, CR2032 coin cell batteries will be fabricated and tested with standard cycling procedures. Besides electrochemical characterization techniques, complementary measurement like real space imaging techniques (scanning electron microscopy, SEM) and reciprocal space techniques (small angle x-ray scattering, SAXS) can be performed. Overall, this master thesis project involves literature review, sample preparation and data analysis.
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AEP |
Low-temperature fabrication of titania films for hybrid solar cells on flexible substrates |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Low-temperature (<150°C) route towards titania films offer promise for simple manufacturing, compatibility with flexible substrates, and titania-based solar cells. Herein, we use a specific titania precursor, ethylene glycol-modified titanate, to fabricate titania films as an electron-transporting layer. This experimental bachelor thesis aims at understanding the working principle of hybrid solar cells and the corresponding fabrication process. Different film characterization will be used such as SEM, GISAXS, XRD, UV-Vis, XPS, etc. The project will involve a literature review, sample preparation process, data analysis and result evaluation.
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KM |
Magnon transport in laterally confined magnetic insulators |
Gross |
- Research group
- Technical Physics
- Description
- In antiferromagnetic insulators, we obtain two magnon modes with opposite spin chirality due to the two opposing magnetic sublattices. In this way, magnon transport in antiferromagnetic insulators can be considered as the magnonic equivalent of electronic spin transport in semiconductors and the properties can be mapped onto a magnonic pseudospin. At present, most experiments rely on extended epitaxial thin films of antiferromagnetic insulators. Your thesis will be dedicated to confine the lateral dimensions of the magnon transport channel. By conducting all-electrical magnon transport experiments, you will then determine the role of lateral confinement in such measurement schemes.
You are interested in providing novel insights into pseudospin properties in antiferromagnetic insulators and provide a spark for theoretical descriptions. In order to answer questions regarding magnon transport in magnetic insulators, your thesis will contain aspects of the fabrication of nano-scale devices using electron beam lithography as well as ultra-sensitive low-noise electronic measurements at high magnetic fields in a cryogenic environment.
- Contact person
- Matthias Althammer
- Matthias Opel
- Hans-Gregor Hübl
- Stephan Geprägs
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AEP |
Masterarbeit: Optische Charakterisierung chiraler Perowskite (topic is not available any more) |
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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KM |
Messung der Zeit-Impuls-Korrelation von Positronen in Materie (AMOC) (topic is not available any more) |
Hugenschmidt |
- Research group
- Neutron Scattering
- Description
The positron is a well-established probe to perform defect sensitive spectroscopy on all kind of materials. Typically, one can measure either the lifetime of the positron or the Doppler shift of the annihilation gamma quanta. Both methods give different insights into the concentration, distribution and size of lattice defects in the material. However, it is also possible to record both the energy shift and the time delay of the annihilation radiation simultaneously. The Age-Momentum Correlation (AMOC) technique combines gamma detection with high energy resolution and high time resolution in order to measure the correlation between positron lifetime and momentum. The thesis comprises the construction of a laboratory AMOC setup including the readout system for the detectors and data treatment. Finally, the setup will be benchmarked using an assortment of reference samples and metal alloys. The project is carried out within the TUM research group Physics with Positrons.
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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 |
Munich Compact Light Source: Development of an algorithmic framework for high-sensitivity grating-based phase-contrast imaging |
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 |
Munich Compact Light Source: 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 |
Near-infrared Quantum Dot Solar Cells for Space Application (topic is not available any more) |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
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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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KTA |
Optical Atomic Magnetometer |
Fierlinger |
- Research group
- Precision Measurements at Extreme Conditions
- Description
Our group is actively developing optical atomic magnetometers, a type of sensors using light-atom interactions to detect magnetic fields.This approach, sitting on the junction of laser-optics, quantum-optics and atom-physics, offer a wide range of possibilities for undergraduate and graduate students, from theoretical approaches to practical experiments.
Possible thesis projects are: the Characterization of a non-magnetic Optical Atomic Magnetometer Array at the panEDM Experiment (at ILL), the Development of a non-magnetic Free Space Cesium Magnetometer, the Development of an Optical Earth Field Cesium Magnetometer, the Characterisation and Improvement of Cesium Vapor Cells and Upgrading and Characterisation of a Magnetically Shielded Test Chamber for Magnetometers.
Students can learn a variety of skills, such as handling laser optics and different measurement systems, designing sensors, or developing operating and analysis software.
If you are interested or want to learn more on this topic - feel free to contact philipp.roessner@tum.de! - Contact person
- Philipp Rößner
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AEP |
Optically controlled automatic sample positioning system for scattering/diffraction applications: conceptualisation and development |
Petry |
- Research group
- Functional Materials
- Description
- Accurate, controllable and reproducible sample positioning is necessary for a variety of experimental techniques utilizing laser, X-rays, electron beams and/or neutrons. For the diffractometers at the FRM II neutron source a fully automatic sample positioning system is required, which, in conjunction with a robotic sample changer, will be the base for an automatized experimental pipeline. The mechanical core of the system will be a stepper motor driven goniometer head from Huber, possessing five degrees of freedom. The movement, detection and control will proceed by a silhouette detection system based on telecentric optics. The tasks of the proposed thesis will include: conceptualisation and building up of telecentric optical control system, the optimisation of data readout, the development of fully automatic alignment algorithm, the integration of the components into NICOS system (Python driven) and the validation of the system in real measurements with neutron scattering and/or synchrotron radiation.
Common supervision is foreseen with Dr. Anatoliy Senyshyn, diffraction group leader at MLZ.
- Contact person
- Anatoliy Senyshyn
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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 |
Printed perovskite solar cells |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Organic-inorganic lead halide perovskite solar cells have recently achieved 25.5% efficiency owing to their tunable bandgap, high carrier mobility and long diffusion length. Nevertheless, most of the solar cells were fabricated based on the spin-coating method, which suffers from waste of material and missing scalability. In this regard, the printing technique, a simple and scalable method, is advantageous to realize a future commercial application of perovskite solar cells. In this project, we aim to fabricate perovskite solar cells by printing and have an overall understanding of the growth mechanism of the perovskite film during printing. We use imaging techniques (e.g. electron microscopy) and methods for structure and morphology determination, e.g. X-ray scattering.
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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 |
Produktion und Test von RPC-Prototypen |
Kortner |
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AEP |
Quantification of local aging behaviour in lithium-ion batteries |
Petry |
- Research group
- Functional Materials
- Description
Quantification of local aging behaviour in lithium-ion batteries
Lithium-ion batteries are nowadays the primary energy storage system in electric driven vehicles and portable electronic devices. Thus, a continuous improvement of lithium-ion batteries is mandatory to meet the increasing energy demand on the market. One of the main branches of today’s research deals with the minimization of aging effects occurring in lithium-ion batteries and taking place during cell operation. In the proposed project, the state-of-health at different areas of a working electrode in real lithium-ion batteries will be determined in order to create a 2D “map” of the state of fatigue distribution. Thus, commercially available lithium-ion batteries will be electrochemically cycled and disassembled in order to harvest the electrode materials. Fragments of the extracted electrodes collected at various positions over the electrode sheets will be analysed as coin cells with various characterization techniques, such as impedance spectroscopy, cycling voltammetry and galvanostatic intermittent titration technique. The project will be completed with X-ray diffraction measurements of the collected electrodes.
Common supervision is foreseen with Dr. Anatoliy Senyshyn, diffraction group leader at MLZ. - Contact person
- Anatoliy Senyshyn
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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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KM |
Simulation der Positronendiffusion bei angelegten elektrischen Feldern zur Bestimmung der Leestellenkonzentration in Festkörpern (LIMPID) |
Hugenschmidt |
- Research group
- Neutron Scattering
- Description
- Positronen können je nach Implantationstiefe im Festkörper zurück an die Oberfläche diffundieren, bevor sie annihilieren. Das resultierende Gammaspektrum – insbesondere die Form der 511 keV Annihilationslinie – ändert sich mit dem Anteil der Positronen die an der Oberfläche annihilieren.
Eine Simulation der tiefenaufgelösten Diffusion erlaubt es uns, die Leerstellenkonzentration in der Probe aus bei unterschiedlichen Implantationstiefen gemessenen Daten zu bestimmen.
Hauptziel der Masterarbeit ist es, den von uns entwickelten Algorithmus zur numerischen Lösung der Diffusionsgleichung in Python zu erweitern, um zusätzliche Effekte, wie variable Defektverteilungen oder elektrische Felder im Inneren der Probe zu berücksichtigen.
Das Projekt wird in der TUM Forschungsgruppe Physik mit Positronen durchgeführt.
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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 photon counting X-ray detectors: Application to panoramic and cone-beam dental CT imaging (topic is not available any more) |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
This project will explore the use of latest hybrid-pixel photon-counting detectors for improving the image quality in 3D (cone-beam CT) dental imaging applications. More specifically, the project aims at the experimental evaluation of the potential benefits of applying spectral material decomposition for dental CT application. The work will include preclinical experiments using dedicated anthropomorphic head phantoms and subsequent image analysis and interpretation. The project will be carried out in close collaboration with the Department of Radiology at the TUM Klinikum Rechts der Isar and with an external industrial collaborator located in the Munich area.
Character of thesis work: experimental physics (30%) & image processing (70%)
For more information, please contact: Daniel Berthe (daniel.berthe@tum.de) or Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Daniel Berthe
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AEP |
Spectral photon counting X-ray detectors: Characterisation of detector performance (topic is not available any more) |
Pfeiffer |
- Research group
- Biomedical Physics
- Description
Hybrid pixel photon-counting detectors have been developed in the past in high-energy physics and are currently used in various medical imaging applications. They offer higher spatial resolution and additional energy resolution and therefore have significant potential for future improvements in radiography and CT. This work will investigate some basic physical properties of the detectors and, in particular, explore the response of such detectors to oblique radiation, which is very important for some spectral imaging applications.
The project is carried out in close collaboration with external partners from industry.
Character of the work: experimental physics (70%) & image processing (30%).
For more information, please contact: Daniel Berthe (daniel.berthe@tum.de) or Franz Pfeiffer (franz.pfeiffer@tum.de)
- Contact person
- Daniel Berthe
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KM |
Spinabhängige Prozesse in der Photokatalyse (topic is not available any more) |
Brandt |
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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 |
Synthesis and self-assembly of gold nanoparticles for optoelectronic devices |
Müller-Buschbaum |
- Research group
- Functional Materials
- Description
- Gold nanoparticles (Au NPs) show peculiar optical and electrical properties compared with the macroscopic metal owing to the characteristic of a nanoscale. Recently many advantages were made in optoelectronic devices applications with broadening band and energy transfer. In this project, your work will focus on the Au NPs structure regulation, since the size, density, and morphology of the Au NPs will influence the crystallinity of the photoactive film and charge transportation of the device. Specifically, you can work on one of the following topics: a) Synthesis and investigate optical properties of different morphology of gold nanoparticles b) Self-assembly of monolayer Au NPs array for optoelectronic devices.
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AEP |
Top-down approach for the synthesis of shape controlled nanoparticles |
Bandarenka |
- Research group
- Physics of Energy Conversion and Storage
- Description
- The thesis focuses on the facile synthesis of nanoparticles (NPs) by electrochemical erosion of different materials. NP can be immobilized on a support for applications in electro- and heterogeneous catalysis. Our unique approach involves applying an alternating voltage to a metal substrate placed in an electrolyte. The “green” method uses no further chemicals and allows controlling shape and size of the NPs adjusting parameters such as applied potential, frequency and electrolyte composition. Different characterization techniques such as TGA, XPS, XRD, SEM etc. will be used for the investigation of prepared materials and performance tests will be conducted.
The contact persons are Dr. Elena Gubanova (elena.gubanova@tum.de) and Christian Schott (christian.schott@tum.de).
- Contact person
- Christian Schott
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KTA |
Two-loop Feynman integrals for single top production at NNLO |
Tancredi |
- Research group
- Theoretical Particle Physics
- Description
Providing higher order QCD corrections to the hadronic production of top quarks at the LHC is an important step towards obtaining a more detailed understanding of electroweak symmetry breaking, due to the fact that top quarks receive their mass through interactions with the Higgs background field. Single top production is one of the most prominent top quark production channels at the LHC, with the t-channel process, which involves the production of a single top quark mediated by an exchange of a W boson, accounting for 70% of all single top quarks produced at LHC collisions. Recently, NNLO corrections to the so-called non-factorisable contributions to the single top t-channel were computed. The calculation was performed by calculating all the relevant 2-loop Feynman integrals numerically. It will be the aim of this project to provide an efficient analytic representation of these integrals in terms of special functions (e.g. multiple polylogarithms), by employing modern methods of multiloop calculations such as integration-by-part identities, canonical differential equations and the study of the relevant special functions. - Contact person
- Nikolaos Syrrakos
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BIO |
Untersuchung der Flexibilität von Amyloidstrukturen mit MD-Simulationen |
Zacharias |
- Research group
- Molecular Dynamics
- Description
- Amyloid structures can form by aggregation of misfolded protein molecules or peptides. These aggregates are involved in several diseases. The various amyloid structures differ in the conformational flexibility and stability. Very flexibile amyloid structures are more likely to disaggregate and can be recognized and eliminated by proteases and immune molecules. Aim of the BSc thesis is to investigate the conformational flexibility and dynamics of different amyloid structures using computer simulations and to understand the physical origin of the dynamics of amyloid structures.
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KTA |
Untersuchung verschiedener Transient-Klassen mittels Fermi/GBM Daten (topic is not available any more) |
Greiner |
- Research group
- Max-Planck-Institue for Extraterrestrial Physics (MPE)
- Description
The recent detection of gravitational waves (GW) with the advanced LIGO/Virgo instruments in conjunction with a short gamma-ray burst (GRB) has surprised gamma-ray astronomers because of the substantially different properties of the GRB signal as compared to canonical GRBs. This motivates an "open-mind" search for untriggered transient events in the data stream of the gamma-ray burst monitor (GBM) on the Fermi satellite. With a previous Master thesis we have developed an automated search for gamma-ray transients in Fermi/GBM data.
This thesis shall improve this new procedure, and establish a Python program for recognizing certain types of transient sources. The work also involves learning about different transient source types, and their X-ray and gamma-ray characteristics.
The project includes elements from computational and observational high-energy astrophysics, and will allow for obtaining extensive knowledge on the broad class of high-energy transients. 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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Aliaksandr Bandarenka and a Master's student in his group discuss about their research. Foto: TUM.PH/Eckert. The research phase constitutes one thematic block, culminating in the dissertation of the Master's thesis.