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2D optomechanics |
Poot |
- Arbeitsgruppe
- Quantentechnologien
- Beschreibung
Optomechanics is an extremely exciting field where the tiniest motions of mechanical resonators are measured with the help of laser light. So far, most of these experiments have been done with beams and cantilevers, in other words with one-dimensional structures. In the Quantum Technologies Lab we have just build a new setup, where we can measure the vibrations of 2D mechanical systems.
The goal of this project is to explore the world of 2D optomechanics. For this, we have two kinds of samples in mind: one is made from silicon nitride, which is a material with extremely high quality factors. This material is not only used in the manufacturing process of chips, but is also a great material to do optomechanics with. The other direction is to use materials that are just a few atoms thick: This includes graphene, boron nitride, and sandwiches of these true 2D materials. For this, we collaborate with the Karlsruhe Institute of Technology.
We will make the samples for you in the cleanroom, and it will be your goal to measure them with our new setup. This includes their optical characterization, as well as electrical measurements in the time domain (oscilloscope) and in the frequency domain (network- and spectrum analyzer). For the measurement and data processing, we already have a range of computer programs available in our group, so that you can start measuring right away. Depending on your preferences, the project could be completely experimental, or also contain a modelling component.
The project is envisioned with students in Applied and Engineering Physics (AEP) and Condensed Matter Physics (KM) in mind, but if you follow another track we are still interested to hear from you. Being curious and wanting to get a feeling for what doing real research is about, is the most important factor. There are no formal requirements on courses taken.
- Forschungsfeld
- Nanostrukturen (experimentell) (~50%)
- Optik (experimentell) (~50%)
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Abschätzung des Einflusses von Auger-Elektronen auf die Photoemissionszeitbestimmung in Attosekunden-Streaking-Messungen |
Kienberger |
- Arbeitsgruppe
- Laser- und Röntgenphysik
- Beschreibung
- In dieser Arbeit soll mittels Simulationen bestimmt werden, in welchem Maße Auger-Elektronen das Ergebnis einer Photoemissionszeitmessung verfälschen können. Diese Arbeit ist damit Teil einer aktuell laufenden Untersuchung der zeitlichen Dynamik der Photoemission in kleinen organischen Molekülen.
- Forschungsfeld
- Quantenoptik (experimentell)
- Betreuer(innen)
- Christian Schröder
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Analysis of backscattering non-linearities in electron energy detectors (Thema ist bereits vergeben) |
Märkisch |
- Arbeitsgruppe
- Elementarteilchenphysik bei niedrigen Energien
- Beschreibung
- We can set new limits on interactions beyond the Standard Model by studying the neutron beta decay. For this, we measure the decay electron energy with scintillator-based detectors and look for deviations in the energy spectrum from Standard Model predictions. The scintillator-based detectors convert electrons into photons, with the number of photons proportional to the original electron energy. Some electrons scatter in the scintillator and leave it without depositing enough energy to create a signal. Even with a second detector to capture backscattered electrons, we are missing energy for these backscattered electrons, and we need to understand the process. For this, we have a large dataset with electron timing information to study the phenomena from a recent measurement campaign at the research reactor Institut Laue-Langevin in Grenoble.
You will use this unique data set and our analysis framework (Python) to help us to model the effect and correct our measurement. You will develop your own analysis with our tools and conduct simulation studies to compare your results.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Max Lamparth
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Analysis of the impedance response of the anode and cathode materials for Li-ion batteries |
Bandarenka |
- Arbeitsgruppe
- Physik der Energiewandlung und -speicherung
- Beschreibung
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Impedance spectroscopy (IS) is one of the most sensitive characterization techniques to obtain knowledge on batteries. This project aims to monitor the changes in the Li-ion cell caused by temperature, c-rate, cycle number, and different active material loading using IS. The main direction will be preparing of so-called half-cells by using anode or cathode active materials. Thereafter, you will monitor and analyze the impedance responses of the cells under different conditions and be able to explain the physics behind the impedance spectra.
This project will involve a literature review, coin cell sample preparation, glovebox usage, impedance spectroscopy, and battery testing.
- Forschungsfeld
- Materialphysik (experimentell)
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Analysis of the Material Properties during Precipitation Hardening of Al Alloys using Positrons |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
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Al alloys play a vital role in structural engineering. Many Al alloys gain their strength from precipitation hardening. The process of precipitate formation in Al alloys, however, is still not fully understood. For this purpose, an AlCuLi alloy is to be investigated using the positron beam at NEPOMUC/FRM II. Coincident Doppler broadening spectroscopy uses the positron as a micro probe in order to gain valuable information of the chemical environment of the positron annihilation site. This allows the investigation of vacancy-solute complexes and the formation of precipitates in Al alloys.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Anwendung von Markov-Chain-Monte-Carlo-Methoden in der Partialwellenanalyse des π⁻π⁻π⁺ Endzustandes in Daten des COMPASS-Experiments (Thema ist bereits vergeben) |
Paul |
- Arbeitsgruppe
- Hadronenstruktur und Fundamentale Symmetrien
- Beschreibung
The partial-wave analysis of multi-body final states such as π⁻π⁻π⁺, which are produced in high-energy scattering reactions, constitutes a challenging statistical inference problem, where models with a large number of parameters are fitted to high-dimensional data using the maximum likelihood method. Up to now, these analyses are based on point estimates that rely on the asymptotic normality of the likelohood function. The goal of this thesis is to test this assumption and to also better understand multimodalities of the likelihood function by applying Markov Chain Monte Carlo methods to this inference problem.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Florian Kaspar
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Aufbau eines Spektrometers für ferromagnetische Resonanz für Frequenzen bis 65 GHz |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
In dieser Arbeit soll ein neues Spektrometer für Messungen mit Methoden der ferromagnetischen Resonanz im Frequenzbereich zwischen 10 - 65 GHz aufgebaut und getestet werden.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Lin Chen
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Batteries. Optimization by pretreatment of Carbon Cloth current collectors for scaled-up mass loadings by electrodeposition |
Bandarenka |
- Arbeitsgruppe
- Physik der Energiewandlung und -speicherung
- Beschreibung
- Energy storage technologies are an indispensable element of the transition towards an eco-friendly society. Due to their low cost, scalability, and non-flammability, aqueous sodium-ion batteries are promising for stationary applications, ranging from photovoltaic-powered private households to large-scale grid electricity buffers. This experimental bachelor thesis will aim at understanding, characterizing, and optimizing intercalation-type battery electrodes. The student will contribute to investigating fabrication methods, electrode substrates, active material composition, self-discharge, and lifetime. The project will involve literature research, experimental training in a laboratory, and hands-on working on battery electrodes and electrolytes.
- Forschungsfeld
- Materialphysik (experimentell)
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Berechnung der freien Energie der Ligand-Protein-Bindung |
Zacharias |
- Arbeitsgruppe
- Molekulardynamik
- Beschreibung
-
Mit Hilfe von Moleküldynamiksimulationen sollen freie Energien der Bindung von einem Liganden an ein Enzymmolekül berechnet werden. Der Ligand hemmt die Aktivität des Enzyms durch Bindung an die aktive Tasche des Enzyms. Durch Simulationsstudien kann der Einfluss einzelner chemischer Gruppen auf die Bindeaffinität (=Stärke der Bindung) des Liganden untersucht werden. Ziel der Simulationsstudien ist es, die Bedeutung einzelner chemischer Gruppen für die Bindeaffinität zu analysieren und mögliche Wege zu Erhöhung der Affinität aufzuzeigen.
- Forschungsfeld
- Biologische Physik (Theorie)
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Binding of gaseous compounds on surface supported metalloporphyrin arrays |
Papageorgiou |
- Arbeitsgruppe
- Oberflächen- und Grenzflächenphysik
- Beschreibung
- For the creation of novel materials and devices, inspiration is frequently sought in nature. Metalloporphyrins are natural compounds and common prosthetic groups to handle respiratory gases, sensing and catalytic functions. Arrays of metalloporphyrin layers under vacuum conditions present a versatile playground for functional interfaces due to the coordinatively unsaturated metal centers.
Complexes of inorganic gaseous molecules, as CO, with metalloporphyrins are important intermediate species in catalytic processes, crucial in chemical processing. We aim to improve the fundamental understanding of these complex systems, in order to enable green chemical production. Hence, we perform model experiments with different metalloporphyrins (e.g. ruthenium octaethylporphyrin or ruthenium tetraphenylporphyrin) on different well-defined metal surfaces (e.g. Ag(111) or Cu(110)). Our methods are, on the one hand, visualization of the porphyrin structures on the metal surface with scanning tunneling microscopy (STM) on a submolecular level. To support these data we use spectroscopic methods, such as X-ray photoelectron spectroscopy (XPS).
The bachelor thesis would focus on adsorption experiments with CO on metalloporphyrins with STM.
- Forschungsfeld
- Oberflächenphysik (experimentell) (~40%)
- Chemische Physik (experimentell) (~20%)
- Nanostrukturen (experimentell) (~20%)
- Festkörperphysik (experimentell) (~20%)
- Betreuer(innen)
- Dennis Meier
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Bioinspired electrodes for brain wave detection |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- With increasing demands in brain computer interfaces measuring biosignals non-invasively becomes more important. Applications like measuring brain waves via electroencephalography (EEG) with dry electrodes remains challenging as for a steady biosignal acquisition adhesion to the skin has to be maintained all the time. The thesis will include the preparation of mussel-inspired hydrogels and the investigation of its conductive and adhesive properties. Furthermore, the EEG-performance of these electrodes will be evaluated with a dedicated setup.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Cavities in white smokers as the cradle of life (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- White smokers are likely the cradle of life. Their caves and tunnels allow reactants to accumulate at catalytic sites to start the reactions at the origin of life. What property makes their caves a hub for reactants? You will simulate transport of reactants in different cavity geometries using the finite element simulation tool Comsol. By varying cavity property and flow conditions in and around the cave you will identify the physical parameters that were prerequisites for the origin of life. You will learn Comsol, fluid dynamic at low Reynolds number. Prerequisites: Joy for numerical experiments
Task 1 Program a simple cavity pinching of from a tunnel with steady supply of reactants and observe how reactants diffuse into the cavity
Task 2 Change cavity geometry to trap reactants and increase reactant concentration
Task 3 Add reactant absorption to the cavity walls to further enhance reactant concentration
- Forschungsfeld
- Biologische Physik (Theorie) (~50%)
- interdisziplinäre Themen (Theorie) (~50%)
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Characterization of Superconducting Connectors for the NUCLEUS Experiment |
Strauß |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- The detection of coherent-neutrino nucleus scattering (CEvNS) opens a new window to study the fundamental properties of neutrinos and to probe physics beyond the Standard Model of Particle Physics.
NUCLEUS is a novel cryogenic neutrino experiment at a nuclear power reactor which allows for precision measurements of CEvNS at unprecedentedly low energies. It is based on recently demonstrated ultra-low threshold cryogenic detectors being developed at TUM. Accessing energies in the 10eV regime enables to fully exploit the strongly enhanced cross section of CEvNS which leads to a miniaturization of neutrino detectors. The NUCLEUS collaboration consists of 5 institutes in Germany, France, Italy and Austria and is fully funded. The experiment will be installed at a new experimental site at the CHOOZ nuclear power plant in France.
In the framework of this thesis, students can directly contribute to the development of the NUCLEUS cryogenic detector at the TUM labs. This work will focus on the characterization of the superconducting cables and connectors of the main component of NUCLEUS, the cryogenic detector.
The Bachelor student will be involved in:
- Precision resistance measurements at cryogenic temperatures (mK)
- Operation of state-of-the-art cryostats
- High-frequency signal processing and analysis
- Basic signal analysis
Students will be guided to the operation of the device in the laboratory, to perform dedicated measurement campaigns and to analyse the data recorded. A background in basic programming is welcome, but not mandatory. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~40%)
- Festkörperphysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~30%)
- Betreuer(innen)
- Nicole Schermer
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Charakterisierung einer XUV Doppelspiegel Einheit für attosekunden Streaking Experimente (Thema ist bereits vergeben) |
Kienberger |
- Arbeitsgruppe
- Laser- und Röntgenphysik
- Beschreibung
- Gegenstand dieser Arbeit ist sowohl das Neu-Design einer geeigneten Halterung für einen XUV Doppelspiegel via CAD, als auch die Charakterisierung zweier energetisch identischer XUV Fokussieroptiken unterschiedlicher Beschichtung hinsichtlich ihres Verhaltens bei der Durchführung von attosekunden Streaking Experimenten an Neon. Es handelt sich um brandaktuelle experimentelle Fragestellungen in der Ultrakurzzeitphysik auf der Attosekunden-Zeitskala.
- Forschungsfeld
- Quantenoptik (experimentell)
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Computersimulation von Methoden zur Tiefenprofilierung mittels Zerstäubung von rauen Oberflächen |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
Die Messung von Konzentrationsprofilen von Elementen als Funktion der Tiefe ist in vielen Bereichen von Physik und Materialwisssenschaft essentiell. Eine wichtige und häufig genützte Klasse von Methoden basiert auf Tiefenprofilierung durch Zerstäubung, d.h. ein Strahl von (typischerweise schweren) Ionen schlägt Atome aus einer Oberfläche heraus und schreitet durch Materialabtrag in die Tiefe fort. Die herausgeschlagenen Atome können durch verschiedene Methoden nachgewiesen werden, z.B. Sekundärionenmassenspektrometrie (SIMS) oder glow discharge optical emission spectroscopy (GDOES). Diese Methoden sind für glatte Oberflächen gut etabliert. Die Anwendung auf rauen Oberflächen dagegen enthält viele offene Fragen und wird seit Jahren kontrovers diskutiert. Die Zunahme von paralleler Rechenleistung während der letzten Jahre erlaubt mittlerweile die dynamische Simulation von Tiefenprofilierungsmethoden mittels Zerstäubung von 2-und 3-dimensional Oberflächen mittels des existierenden Programms SDTrimSP. Erste Ergebnisse zur Evolution von rauen Oberflächen durch Zerstäubung wurden bereits in einer Bachelorarbeit erzielt. Diese Arbeit soll weitergeführt werden und zu einem besseren Verständnis des Zerstäubungsprozesses von rauen Oberflächen führen.
Contact: Dr. Matej Mayer
- Forschungsfeld
- Plasmaphysik (experimentell)
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Conductive paper |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Transparent flexible substrates with electrical conductivity are an essential component for display technologies of devices like smartphones. In organic photovoltaics the use of flexible substrates allows for applications with a new versatility. We follow an environmentally friendly approach with the use of nanocellulose derived from wood in combination with conductive polymers. This project comprises the preparation of composite films with printing technology and the characterization of conductivity and optical properties.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Cononsolveny unter Druck - lösen oder nicht lösen? |
Papadakis |
- Arbeitsgruppe
- Physik der weichen Materie
- Beschreibung
- Thermoresponsive Polymere sind in Wasser bis zu einer bestimmten Temperatur löslich, werden dann abrupt unlöslich und aggregieren. Die Übergangstemperatur sinkt stark ab, wenn ein Alkohol zugegeben wird. Dieses Phänomen heißt Co-nonsolvency. Unter Druck ist diese Temperatur allerdings wieder erhöht, was mit der Wechselwirkung der Polymere mit Wasser und Alkohol zu tun hat, aber noch unverstanden ist. In dem Bachelorprojekt sollen Phasendiagramme neuartiger thermoresponsiver Polymere in Wasser-Alkohol-Mischungen an unserer Hochdruckanlage gemessen werden.
Nach einer Literaturrecherche sollen Proben präpariert werden und die Phasendiagramme gemessen werden. Die Daten sollen analysiert und interpretiert werden. Für weitere Informationen kontaktieren Sie bitte Prof. Christine Papadakis, papadakis@tum.de.
- Forschungsfeld
- Polymerphysik (experimentell)
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Controlled Fabrication of Chiral Lead-Free Perovskites |
Deschler |
- Arbeitsgruppe
- Experimentelle Halbleiterphysik
- Beschreibung
The Deschler group at the Walter Schottky Institute of TU Munich invites applications for
Bachelor/Master Projects on Controlled Fabrication of Chiral Lead-Free Perovskites
The group
The Deschler group is an independent research group at Walter Schottky Institute of TU Munich, established through the DFG Emmy-Noether Program and an ERC starting Grant. Our research focuses on the ultrafast dynamics of functional materials and their applications energy applications. More information can be found on our website at https://www.wsi.tum.de/views/sub_group.php?group=Deschler&sub_page=home
Your projects
Hybrid organic inorganic perovskites are optoelectronic materials with tunable chemical and electronic structures. Incorporating chiral organic molecules into perovskite networks also attracts great attention due to their potential optical communication applications. Nevertheless, most reported chiral perovskite materials possess highly toxic Pb, which potentially limits their practical applications. In this project, your work would focus on introducing chiral organic molecules into hybrid lead-free perovskite, and grow corresponding high-performance single crystals and thin films. You will spearhead the design and fundamental understanding of novel functionality in materials. Specifically, you can work on one of following topics:
· Designing chiral lead-free perovskites with different chiral organic molecules
· Incorporating MA, FA, or Cs into chiral lead-free perovskites to get different layers samples
· Transition metal doping on chiral lead-free perovskites to acquire magnetic properties
During your Bachelor or Master project in our group, you will have the chance to gain hands-on experience in the solution-/vapor-based synthesis of novel functional materials, a range of state-of-the-art spectroscopic, optoelectronic and diffraction tools, as well as detailed understanding of the physics of functional semiconductors. Dedicated support from a PhD student or postdoc will be available during your project. You will be expected to make scientific discoveries and contribute to the dynamic atmosphere of our group.
Your Application
Applications should be sent to felix.deschler@tum.de. Please include your CV, and other related documents. Looking forward to your applications!
- Forschungsfeld
- Festkörperphysik (experimentell)
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Cooking up life in the white smoker (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- White smokers are likely the cradle of life. Their caves and tunnels allow reactants to accumulate at catalytic sites to start the reactions at the origin of life. How do these catalytic sites form and grow with the smoker? You will grow two-dimensional smokers on a microfluidic chip and measure the smoker geometry from your data. You will learn about microfluidics, microscopy, Matlab, image analysis and the fluid physics of laminar flow in flow networks.
Prerequisites: Statistical physics and fascination for the wonders of nature.
Task 1 Learn and improve the experimental setup to control the microfluidic device for smoker formation
Task 2 Experimentally explore the morphologies of smokers as you vary inflow rate and inlet geometry
Task 3 Quantify smoker morphology with respect to the flow network geometry within the smoker. Built a hypothesis which physical conditions favor the formation of caves as catalytic sites.
- Forschungsfeld
- Biologische Physik (experimentell) (~50%)
- Chemische Physik (experimentell) (~30%)
- interdisziplinäre Themen (Theorie) (~20%)
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CRESST: Freezing cold, deep underground, illuminating the dark (matter) |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
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 students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Festkörperphysik (experimentell) (~30%)
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Cryogenic Properties of Detector Materials for the NUCLEUS Experiment |
Strauß |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
-
The detection of coherent-neutrino nucleus scattering (CEvNS) opens a new window to study the fundamental properties of neutrinos and to probe physics beyond the Standard Model of Particle Physics.
NUCLEUS is a novel cryogenic neutrino experiment at a nuclear power reactor which allows for precision measurements of CEvNS at unprecedentedly low energies. It is based on recently demonstrated ultra-low threshold cryogenic detectors being developed at TUM. Accessing energies in the 10eV regime enables to fully exploit the strongly enhanced cross section of CEvNS which leads to a miniaturization of neutrino detectors. The NUCLEUS collaboration consists of 5 institutes in Germany, France, Italy and Austria and is fully funded. The experiment will be installed at a new experimental site at the CHOOZ nuclear power plant in France.
In the framework of this thesis, the cryogenic properties of detector materials are investigated. This work will focus on the measurement of the heat capacities of different crystalline and plastic scintillator materials, which values are widely unknown and of high interest for the NUCLEUS experiment as well as for the scientific community. The results are expected to lead to a scientific publication on the topic.
The Bachelor student will be mainly involved in:
* Development of a device for heat capacity
measurements
* Setting up and performing measurements in a
cryostat
* Analysis of the taken data
Students will be guided to the operation of the dilution refrigerator cryostats at TUM , to preform heat capacity measurement campaigns and to analyse the data recorded. A background in basic programming is welcome, but not mandatory. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~20%)
- Festkörperphysik (experimentell) (~50%)
- Teilchen und Felder (experimentell) (~30%)
- Betreuer(innen)
- Alexander Wex
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Datenanalyse zur Bestimmung der Zeitprofile und Quenchingfaktoren von neuen Szintillatoren für zukünftige Neutrinoexperimente |
Oberauer |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- Weltweit werden z.Z. neuartige Flüssigszintillatoren als Nachweismedien für zukünftige Neutrinoexperimente bei niedrigen Energien (im MeV-Bereich) und an Beschleunigern (im GeV-Bereich) entwickelt. In dieser BSc-Arbeit werden Daten zweier Strahlzeiten analysiert, die am Beschleuniger in Padua (Ita) aufgenommen wurden. Dabei wurden verschiedene Szintillatoren mit gepulsten Gamma- und Neutronenstrahlen bombardiert, die für die Projekte JUNO, JUNO-TAO (China) und THEIA (USA) in Frage kommen. Ziel der BSc-Arbeit ist die Bestimmung wichtiger Eigenschaften dieser Szintillatoren, wie z.B. die Zeitprofile der Emission der Photonen oder die sogenannten Quenchingfaktoren, welche die Abhängigkeiten der Intensität der Szintillation von Teilchenart und Energie beschreiben. Weitere Details nach Absprache. Mitbetreuer ist Raphael Stock.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Matthias Raphael Stock
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Design and Commissioning of a Temperature Control System for the Characterization of Wavelength Shifters at Low Temperatures |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- Experiments searching for dark matter or neutrinoless double-beta decay commonly use liquid Argon (LAr) as a target or instrumented shielding medium. Particle interactions in LAr produce vacuum-ultraviolet (VUV) light flashes peaking at 128 nm, which are converted to longer wavelengths by wavelength shifters (WLSs). Due to the short LAr scintillation wavelength and low LAr temperature (87 K), the characterization of WLSs requires VUV optics and a cooling system in vacuum. The VUV spectrofluorometer setup used for the characterization of WLSs is currently upgraded to cool the samples by mounting them on the coldhead of a Gifford-McMahon cryocooler in a vacuum-tight sample chamber.
For the characterization at LAr temperature it is crucial to precisely control the sample temperature. The task of this project is to design and commission a temperature readout and control system. The candidate will assess the currently used temperature readout setup and combine it with a new heater system to regulate the temperature. The goal is the implementation of the system into the main data acquisition (DAQ) program of the VUV spectrofluorometer. After the commission of the new temperature control system, the candidate will characterize wavelength shifting materials used in the neutrinoless double-beta decay experiment LEGEND (https://legend-exp.org) at low-temperatures with VUV excitation for the first time.
Existing skills in python and arduino programming are advantageous but not necessary. A high motivation for hands-on work in a spectroscopy laboratory and an affinity for electronics and microcontroller are beneficial. The candidate awaits a diverse project, which offers the possibility to acquire skills in VUV optics, vacuum engineering, cooling technology, sensors and microcontrollers, python and arduino programming, laboratory work and project management.
Supervision at the Physics Deptartment by Prof. Schönert and Andreas Leonhardt. Please contact schoenert@ph.tum.de or andreas.leonhardt@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Andreas Leonhardt
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Designing vasculature on a chip (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Vascular disease are a prime cause of death, understanding malfunctioning of human vasculature is therefore critical. Growing vasculature on microfluidic chips may help to quickly assess drug impact on vasculature and even tumor vascularization. Yet, how do we need to design our microfluidic chips to guide human-like vascular formation? You will employ Comsol simulations to assess how microfluidic design determines the supply of the enclosed vasculature. Your design optimizing vasculature supply of will be implemented directly in our experiments. You will learn about tissue engineering, Comsol. Prerequisites: strong biology affinity
Task 1 Implement our existing microfluidic design in Comsol
Task 2 Assess how the positioning of pillars and supply channels within the microfluidic chips impact the transport of resources
Task 3 Optimize designs for either homogeneous or focused supply to initiate uniform or tree-like vascularization
- Forschungsfeld
- Biologische Physik (Theorie) (~80%)
- Biologische Physik (experimentell) (~20%)
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Designing vasculature on a chip (Thema ist bereits vergeben) |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Vascular disease are a prime cause of death, understanding malfunctioning of human vasculature is therefore critical. Growing vasculature on microfluidic chips may help to quickly assess drug impact on vasculature and even tumor vascularization. Yet, how do we need to design our microfluidic chips to guide human-like vascular formation? You will employ Comsol simulations to assess how microfluidic design determines the supply of the enclosed vasculature. Your design optimizing vasculature supply of will be implemented directly in our experiments. You will learn about tissue engineering, Comsol. Prerequisites: strong biology affinity
Task 1 Implement our existing microfluidic design in Comsol
Task 2 Assess how the positioning of pillars and supply channels within the microfluidic chips impact the transport of resources
Task 3 Optimize designs for either homogeneous or focused supply to initiate uniform or tree-like vascularization
- Forschungsfeld
- Biologische Physik (Theorie) (~80%)
- Biologische Physik (experimentell) (~20%)
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Design of a scintillation detector as primary detector for PERC (Thema ist bereits vergeben) |
Märkisch |
- Arbeitsgruppe
- Elementarteilchenphysik bei niedrigen Energien
- Beschreibung
- 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.
Within this project, the student will design and assemble the first primary detector for PERC and possibly commission it. The performance of the detector will be studied with simulations.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Karina Bernert
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Development of novel X-ray fluorescence sources for Dark Matter and neutrino experiments |
Strauß |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- Searches for light Dark Matter and studies of coherent neutrino scattering (CEvNS) requires a precise understanding of the detector response at energies as low as a few tens of 10eV. In our research group at TUM we are involved in the CRESST experiment for direct Dark Matter Search at the Gran Sasso underground laboratory in Italy and the NUCLEUS experiment for the exploration of CEvNS, to be installed at the CHOOZ nuclear power plant in France. In the framework both projects were are developing innovative calibration sources based on X-ray florescence. X-ray photons from well-known sources (e.g. Fe-55) are irradiated on different target materials consisting of light elements. The subsequent de-excitation of discrete energy levels in the target materials lead to characteristic low-energy X-ray emission which can be used to calibrate the low energy regime of our detectors.
While the proof-of-concept of this project has been achieved, the group at E15 is currently working on an optimization, miniaturization and on applications of these novel calibration sources. In the framework of this Bachelor thesis, the student will perform a dedicated simulation baaed on an existing GEANT4 Monte-Carlo toolkit and then optimize the sources in terms of X-ray yield and energy. In a second step, the optimized source will be build and operated in the dedicated detector setup being installed at TUM.
Students will be introduced to the basics of Monte-Carlo simulations and X-ray florescence, and to will be guided to perform X-ray measurements at TUM and to analyse the data recorded. A background in basic programming is welcome, but not mandatory. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Teilchen und Felder (experimentell) (~40%)
- Festkörperphysik (experimentell) (~20%)
- Astrophysik (experimentell) (~40%)
- Betreuer(innen)
- Victoria Wagner
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Direct imaging of high-intensity positron beams with CCDs |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- NEPOMUC provides the world’s highest intensity of low-energy positrons. The positron beam is applied for defect studies in materials science, surface investigations and fundamental research. Steering and optimization of the positron beam requires the use of beam monitors; ideally they should be fast, precise, reliable and inexpensive enough for them to be deployed in large numbers. Particle beam imaging is traditionally performed by amplifying the signal with micro channel plates, converting it through phosphor screens and then by recording the resulting image using a camera. Improvements in commercial charge-coupled devices (CCDs) and recent measurements on the conversion efficiency of positron beams by phosphor screens suggest, instead, the possibility of directly imaging the particle beam by modifying a CCD detector and placing it in the path of the positron beam. Preliminary measurements performed by our team seem to confirm this hypothesis. Your task will be that of working with the NEPOMUC team to further investigate the feasibility of imaging a positron beam by means of a modified commercial CCD detector.
- Forschungsfeld
- Festkörperphysik (experimentell) (~60%)
- interdisziplinäre Themen (experimentell) (~40%)
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Diskretisierung der Eichsymmetrie der starken Wechselwirkung (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
With the recent rapid development of quantum computers, it has become reasonable to explore the possibilities quantum computers may offer in simulating strong interactions. However, to accommodate the relatively low performance of quantum computers in the foreseeable future, certain approximations to the theory of strong interactions, known as quantum chromodynamics (QCD), have to be made. One option is to discretize the underlying non-abelian gauge symmetry group on which QCD is built. In this project, the theoretical foundations of this approach should be worked out first. The discretization procedure leads to approximation errors which must be understood for practical applications. In the second part of the project, the errors induced by such discretizations should be investigated together with how physical observables can be recovered from simulations with approximated theory inputs.
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Yao Ji
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Doping of thermoelectric polymer films |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Thermoelectric device transform waste heat into electricity and thereby are essential in energy saving in the future. Doping of the polymer blend PEDOT:PSS is known to improve its thermoelectric (TE) performance. In this work, PEDOT:PSS is doped with different zwitterions, and their effect on the relationship of structure-properties of the films is characterized. It can be expected that the zwitterions can effectively induce a charge screening between PEDOT and PSS and consequently lead to significant conductivity enhancement, while the enhancement in the Seebeck coefficient is ascribed to the dipole moment of zwitterion and the interfacial dipole moment formed at the surface of the PEDOT:PSS films. Our findings will provide an understanding of the zwitterion-treated modification for PEDOT:PSS films which will be important for TE device applications.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Dosis-Akkumulation und adaptive Bestrahlungsplanung bei Behandlung mit der Tomotherapie (Thema ist bereits vergeben) |
Wilkens |
- Arbeitsgruppe
- Professur für Medizinische Strahlenphysik (Prof. Wilkens)
- Beschreibung
-
Cancer patients undergoing radiation therapy are treated every day over several weeks. The treatments plan is calculated based on a kilovoltage planning CT. Prior to each treatment, an image is acquired with the megavoltage treatment beam each day. With a special software tool, the original irradiation plan can be recalculated on the actual image of the patient. The anatomy of the patient can change over time and thereby also the size and position of the internal organs. The recalculation of organ doses and tumor doses can provide insight into the actually delivered dose. By analyzing these changes for different tumor entities, a recommendation could be given for the need of adaptive replanning during radiation therapy. Your task is to implement the software and the workflow for the described process as well as to analyze the results.
In this thesis, you can gain an insight into clinical medical physics and learn how to calculate treatment plans for radiation therapy as well as help to improve standard treatment planning procedures.
Contact: Frauke Alexander, frauke.alexander@tum.de, 089-4140-9428
- Forschungsfeld
- interdisziplinäre Themen (experimentell) (~50%)
- interdisziplinäre Themen (Theorie) (~50%)
- Betreuer(innen)
- Frauke Alexander
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Dynamical decoupling and noise spectroscopy with superconducting qubits |
Filipp |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- The characterization and mitigation of decoherence sources in qubits is crucial for quantum computing applications. Decoherence of a quantum superposition state arises from the interaction between the system and the uncontrolled degrees of freedom in its environment. The qubit decoherence is characterized by two rates: a longitudinal relaxation rate Γ1 due to the exchange of energy with the environment, and a transverse relaxation rate Γ2 = Γ1/2 + Γϕ which contains the pure dephasing rate Γϕ. Irreversible energy relaxation can only be mitigated by reducing the amount of environmental noise, reducing the qubit’s internal sensitivity to that noise, or through multi-qubit encoding and error correction protocols. In contrast, dephasing is in principle reversible and can be refocused dynamically through the application of coherent control pulse methods. In this work we are going to investigate different sources of noise and decoherence and how dynamical-decoupling techniques such as CPMG can change the dephasing effects of low-frequency noise on a superconducting qubit.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Quantenoptik (experimentell) (~50%)
- Betreuer(innen)
- Ivan Tsitsilin
- Gleb Krylov
- Malay Singh
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Dynamic patterns of plant development |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Plants mainly develop all their organs like leafs and flowers continuously at their stem. How can the patterning underlying the positioning of these organs at the plant shoot be so robust? You will investigate with numerical simulations the patterning at the tip of the plant shoot and study how variations in cell size and cell number at the shoot impact patterning. You will learn python, pattern formation, mechanics. Prerequisites: Enjoy programming
Task 1 Generate different cell geometries on a spherical shell by getting to know our plant simulation code
Task 2 Run our pattern formation simulation on the cells and program measures that characterize the patterns you observe
Task 3 Quantify how cell geometry impacts pattern formation
- Forschungsfeld
- Biologische Physik (Theorie) (~50%)
- interdisziplinäre Themen (Theorie) (~50%)
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Dynamik im stark korrelierten Hubbard Modell |
Knap |
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Elektrischer Nachweis einer Domänenwand in FeCo-Schichten |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
In diesem Projekt soll der anisotrope Magneto-Widerstand verwendet werden um eine einzelne Domänenwand in ferromagnetischen Nanostrukturen aus FeCo zu detektieren.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Takuya Taniguchi
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Entwicklung eines Teilchendetektors zur Messung von Quenchingfaktoren in flüssigen Szintillatoren (Thema ist bereits vergeben) |
Oberauer |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- Die Suche nach dem Zerfall eines Protons in ein Kaon und ein Anti-Neutrino ist eines der Ziele des zukünftigen JUNO Projekts (20 kt Flüssigszintillator-Neutrinodetektor). Dazu soll der Quenchingfaktor des Kaons bestimmt werden, mit dem die Lichtausbeute als Funktion der Energie beschrieben wird. In der BSc-Arbeit wird an der Entwicklung eines Detektors (Maße ca. 120cm x 15 cm x 15cm) mitgearbeitet, der den Quenchingfaktor im relevanten Energiebereich (ca. 50 bis 500 MeV) mit Teilchen aus einem Beschleuniger möglichst genau bestimmen soll. Details der Arbeit nach Absprache. Mitbetreuerin: Ulrike Fahrendholz.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Ulrike Fahrendholz
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Entwicklung selbstriggernder Driftrohrkammern |
Kortner |
- Arbeitsgruppe
- Hadronenstruktur und Fundamentale Symmetrien
- Beschreibung
- Zylindrische Driftrohre sind bestens für die genaue Vermessung der Myonspuren in großen Teilchendetektoren wie dem ATLAS-Detektor am LHC geeignet. Dabei hinterlassen die Myonen im Zählgas der Driftrohre eine Ionisationsspur, deren Abstand aus der Zeit zwischen dem Teilchendurchgang und dem Zeitpunkt des Driftrohrsignals bestimmt werden kann. Bisher werden schnelle Triggerkammern oder Szintillationszähler für die Bestimmung der Teilchendurchgangs verwendet. In der Bachelorarbeit soll ein Konzept für den triggerlosen Betrieb der Driftrohrkammern ausgearbeitet und mit einer ATLAS-Driftrohrkammer getestet werden. Während der Arbeit besteht die Möglichkeit der Teilnahme an Teststrahlmessungen am CERN.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Entwicklung und Test eines digitalen Verfahrens zur Korrektur von Impulsbodenschwankungen in Signalen in Myondriftrohrkammern |
Kortner |
- Arbeitsgruppe
- Hadronenstruktur und Fundamentale Symmetrien
- Beschreibung
- Driftrohrkammern werden zur genauen Spur- und Impulsmessung im Myonspektrometer des ATLAS-Detektors am LHC eingesetzt. Neben den Myonen sind die Driftrohrkammern einen riesigen Gammastrahlungsuntergrund ausgesetzt. Etwa 1% der Photonen der Gammastrahlung kann über den Comptoneffekt Elektronen aus den Rohrwänden der Driftrohre herausschlagen, die zu Untergrundtreffern führen. Die Signal der Untergrundtreffer können die eigentlichen Myonsignale überlagen. Dabei kommt es auch zu einer Verschiebung des Impulsbodens der Driftrohrsignale, was zu Nachweisverlusten und einer Verfälschung der Signalzeitmessung führen kann. In der Bachelorarbeit soll ein Verfahren ausgearbeitet und getestet werden, bei dem die zur Signalermittlung verwendeten Diskriminatorschwellen nicht konstant, sondern dem Signalverlauf angepasst werden. Hierzu werden simulierte Daten, aber auch Daten, die mit einer ATLAS-Driftrohrkammer aufgenommen werden, zum Einsatz kommen. Es besteht die Möglichkeit, während der Bachelorarbeit an Teststrahlmessungen am CERN teilzunehmen.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Erweiterung eines Spektrometers zur Messung der Positronenlebensdauer zur Bestimmung des freien Volumens in Kaffeebohnen |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Die Messung der Lebensdauer von Positronen (PALS) ist eine etablierte Methode zur Untersuchung von Defekten in kristallinen Materialien oder Nanoporen in Polymeren. Gemessene Positronenlebensdauern betragen typischerweise 100-200 ps. Unser PALS Spektrometer besteht aus einer Na-22 Quelle und schnellen Szintillationsdetektoren, deren Ausgabesignale mit einer Rate von 40 GSamples/s digitalisiert werden. Die Verarbeitung der so erzeugten Daten erfolgt offline durch einen Python-Code. Im Verlauf der Bachelorarbeit soll der Versuchsaufbau routinemäßig mit vier Detektoren betrieben werden. Um die Leistungsfähigkeit des Spektrometers zu demonstrieren, soll eine Messreihe zur Porengröße in Kaffeebohnen in Abhängigkeit des Röstgrades durchgeführt werden.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Erzeugung von Dunkelmaterie im frühen Universum: Konversion versus Annihilation (Thema ist bereits vergeben) |
Garny |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
- Dark Matter represents an important component in the composition of the Universe, and numerous observations
point at its existence. Dark Matter could consist of a so far unknown particle species.
Its interaction with known particles of the Standard Model can explain the production of Dark Matter in the
Early Universe. In this work, the dynamics of the particle reactions resulting from such interactions in the
Early Universe is studied. The aim is to determine the mass and coupling strength that can explain the measured
abundance of Dark Matter in models with several new particle species. Starting from the well known thermal
freeze-out of annihilation processes, an extension featuring conversions as well as annihilations is being
studied.
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Mathias Garny
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Forschung zur Protonenstruktur |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- The student will perform tests of a new analysis package for the analysis of proton structure. The first task will be to familiarize yourself with how the densities of quarks, antiquarks and gluons are described in protons. Then, simulated data will be generated based on known input densities, and the analysis package will be used to extract densities. These will then be compared to the input to see how well the reconstruction can be performed.
The software analysis package is written in the modern language Julia. It is a high-level language and easy to learn.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Gamma Flashes von klassischen Novae (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Classical novae are thermonuclear explosions on the surfaces of white dwarfs, caused by accretion of matter from a companion star. About 10 novae are detected in optical light every year in the Milky Way. In such events, light and intermediate mass nuclei are produced through explosive nucleosynthesis mostly via hydrogen-burning. Several of these nuclei are radioactive and decay on time scales of minutes, which is expected to result in an hour-long gamma-ray flash from electron-positron annihilation. The spectrometer SPI onboard the INTEGRAL satellite could detect these gamma-rays but despite years of measurements, novae have never been observed.
In this thesis, a newly developed method to handle the strong instrumental background in SPI shall be used to perform a retrospective search for gamma-rays in known novae. The new method enhances the sensitivity of our these measurements which may uncover a previously hidden signal.
The main work of this thesis includes 1) understanding classical novae, 2) learning INTEGRAL/SPI data analysis, 3) selecting suitable candidate sources from literature, 4) creating template models (time variable gamma-ray spectra) from available literature, 5) conducting the search. 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
- Forschungsfeld
- Astrophysik (experimentell)
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Gravitative "Atome" (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
A condensate made of very light bosons can be bound gravitationally to a black hole. In a certain approximation, the bound state resembles a bound state held together by the Coulomb force (hence, "gravitational atoms"). The first part of this projects consists in understanding these results and approximations by solving the classical field equation in the background of the curved space-time of a rotating black hole. In the second part recent work is reviewed that discusses how the companion in a binary system can induce transitions between the levels of the gravitational atom, or "ionize" it.
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Julian Strohm
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High efficiency organic solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Organic solar cells have gained significant improvements via novel organic synthesis methods and optimized fabrication routes, especially with respect to their potential roll-to-roll processing for large-area device manufacturing. Printing technique, such as slot-die printing, allows for up-scaling to industrial-oriented scale, which is not the case for laboratory deposition techniques like spin coating. This experimental bachelor thesis aims at understanding organic solar cell working principle and the corresponding fabrication process of solar cell via advanced slot-die printing technique. Besides, the relationship between its efficiency and morphology will be investigated by different measuring technique, such as AFM and small angle x-ray scattering. The project will involve a literature review, sample preparation process, data analysis and result exhibition.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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HPGe characterization for the Monument experiment |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- Learning skills:
Gamma spectroscopy; usage of HPGe detector, DAQ, low-level analysis
Hardware and management in experimental physics
Requisites:
Being comfortable with laboratory “hand-work”
Being communicative and willing to do team-work
Commitment
Physics topics:
0𝜈ββ-decay, accelerator physics, experimental-techniques, ordinary muon capture, HPGe detectors…
Gamma spectroscopy is a powerful tool to evaluate with outstanding resolution the energy and time of radiation in the MeV regime. This is usually realised by the use of High Purity Germanium Detectors (HPGe) cooled down at liquid nitrogen temperatures (77K). Learning how to operate HPGe detectors is a very valuable skill to gain, given the use of HPGe detectors in astroparticle physics experiments, where gamma spectroscopy is a technique widely used in their searches. As an example, the neutrinoless double beta decay (0𝜈ββ-decay) experiments GERDA (https://www.mpi-hd.mpg.de/gerda) and LEGEND (https://legend-exp.org) work under this principle.
The Monument experiment is measuring ordinary muon capture (OMC) in several double beta decay (2𝜈ββ) isotopes used for 0𝜈ββ-decay experiments. These measurements involve the emission of muonic x-rays (µX) and gammas (γs) which are captured by an array of HPGe detectors. To evaluate their energy and time distributions, the Monument experiment uses gamma-spectroscopy. These measurements are performed at the Paul Schrrer Institute, in Switzerland, where a µ-beam fulfilling our requirements for the experiment is available.
At TUM, in the GERDA-LEGEND group, we work on the characterisation of the experimental setup used for the Monument experiment. This involves the characterisation of the HPGe detectors to be used during the beam-time campaigns.
The bachelor student working on this project, is expected to characterise a HPGe detector from the setup and get familiarised with all the experimental elements needed to perform this task; the electronics, the analysis of a gamma-spectrum, the characteristics of this kind of detector, etc. The thesis would include a potential contribution in the up-coming beam-time campaign, in Switzerland, programmed for June 2022.
Supervision at the Physics Deptartment by Prof. Schönert and Elisabeth Mondragon Cortes. Please contact schoenert@ph.tum.de or elizabeth.mondragon@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Elizabeth Mondragon Cortes
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Improving qubit coherence times by surface engineering |
Filipp |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Characterization of surfaces is currently a hot topic for the fabrication of superconducting quantum processors. One way to determine surface properties is the measurement of the contact angle of a deionized water droplet on the surface of differently fabricated chips. For this purpose a measurement setup will be built within this thesis. Afterwards the images will be analyzed using a software called "ImageJ" to extract the contact angle between the chipsurface and the droplet. To compare the results from contact angle measurements to qubit performance, qubit chips will be fabricated and measured at cryogenic temperatures.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Leon Koch
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In Search of the Lowest Radioactive Traces Ever: Tagging BiPo Events in GERDA |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- ll experiments have background - may it be cosmogenic muons, accidental coincidences, or decays from unstable isotopes. A common type of background comes from radiogenic nuclei as part of longer decay chains. These nuclei might be intrinsic to the detector material or might even cause background by being present in the walls around the experiment.
One way of estimating the impact of one such decay chain intrinsic to the detector is the so-called BiPo analysis. The isotope 214Bi which is part of the decay chain of 238U has a high likelihood to decay via beta decay into 214Po which itself decays via alpha decay after only several hundred microseconds. As both of these decays are very highly energetic and their decays so fast after one another, their coincidence signature is often used to estimate the activity of the total decay chain.
For planned experiments, it is vitally important to estimate the impact of specific background sources. The LEGEND-1000 (https://legend-exp.org) experiment, a planned neutrinoless double beta-decay experiment, will use high purity germanium (HPGe) detectors made out of 92% 76Ge which decays via double beta-decay. The question is now how high is the contribution of radiogenic isotopes in Germanium detectors. For this, we can look at the GERDA experiment (https://www.mpi-hd.mpg.de/gerda), another neutrinoless double beta-decay experiment that used HPGes and which was completed recently. In its data, one can look for signals similar to the BiPo coincidences and with that make an estimate of how large of an impact the radiogenic background sources might have for an experiment with a similar setup.
The student will work with raw GERDA data to look for the specific signature of the BiPo decays. This will include learning how the data analysis process looks like for a large experiment - from initial waveform analysis to energy estimation to final event selection. Furthermore, the student will also produce pseudo data to estimate the efficiency to find the BiPos with the proposed analysis. The analysis is performed using C++ and ROOT, so basic knowledge of these languages may be useful, but is not required.
Supervision at the Physics Deptartment by Prof. Schönert and Moritz Neuberger Please contact schoenert@ph.tum.de or Moritz.Neuberger@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Moritz Neuberger
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Ionisiert das GRB Nachleuchten die Muttergalaxie? (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are transient objects bright in gamma-rays that result from an intense relativistic stellar explosion. As this explosion expands, it begins to sweep up the surrounding interstellar gas which shines X-rays (so-called afterglow). It has been proposed that these energetic photons could rapidly ionize this interstellar gas as they propagate through it, resulting in a change in the photo-electric absorption properties of gas for later arriving afterglow photons. Such a process would provide a unique scenario in which changing absorption properties would confuse existing analyses of the intrinsic GRB afterglow spectrum and evolution and thus point to alternative theories about how these relativistic blast waves expand and radiate. To investigate this, new models that incorporate such changes in the absorption must be developed.
This thesis will involve gathering the time evolving X-ray spectra of GRB afterglows observed by Swift XRT and fitting their evolving spectra with existing Bayesian hierarchical modeling software to test the hypothesis that the interstellar gas is ionized during the evolution of the afterglow emission. The modeling will be first tested against simulations of the data and then applied to real data. Discovery of a real change in the ionization state of the gas could potentially lead to a new models of GRB afterglows.
Technically, this thesis involves (i) understanding GRB afterglows and their obscuration by interstellar gas, (ii) simulations of GRB afterglows and the creation of synthetic X-ray data, (iii) analysis of big-data sets via hierarchical Bayesian modeling, (iv) acquisition and reduction of XRT X-ray spectra (v) communication of results and advanced data visualization.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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Korrelationen zwischen GRB Parametern (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are transient objects bright in gamma-rays that, unlike supernovae, pierce through intergalactic dust from the far reaches of the Universe. Thus, they provide a promising tool to probe high-redshift star formation and/or cosmological evolution. To serve as probes, however, the emission from GRBs must be transformed into a so-called “standard candle”, allowing researchers to intrinsically know the true luminosity of the GRB so that its apparent luminosity can be used to derive its distance. Following the path of research in standardizing supernovae, researchers use correlation between the observed properties of GRBs to try and construct relations between those properties and the true luminosity of the GRB.
This thesis will investigate these correlations and their validity through Bayesian hierarchical modeling. This shall be done by creating a simulation of GRBs in the Universe and comparing past methods with newly developed statistical methods which will evaluate (i) if the past methods are correct and (ii) if the new methods enable viable standardization of GRBs and thus a better tool for measuring cosmological parameters.
Technically, this thesis involves (i) understanding GRBs and their use as cosmological probes, (ii) simulation of a population of GRBs with existing software, (iii) analysis of big-data sets via hierarchical Bayesian modeling, (iv) communication of results and advanced data visualization. Background in astronomy is advantageous. Strong programming skills in python and/or C++ is required as well as basic data visualization skills.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
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LEGEND: Why does matter prevail over antimatter in today's Universe? |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- 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 students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~20%)
- Teilchen und Felder (experimentell) (~30%)
- Kernphysik (experimentell) (~30%)
- Festkörperphysik (experimentell) (~20%)
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Low-temperature fabrication of titania films for hybrid solar cells on flexible substrates |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- 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.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Manipulation der Spin-Orbit-Wechselwirkung an Grenzflächen durch Beeinflussung der elektronischen Zustandsdichte (Thema ist bereits vergeben) |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- Durch das Anlegen eine Gate Spannung an eine (Ga,Mn)As/GaAs Heterostruktur kann die elektronische Zustandsdichte verändert werden. Wir wollen hier die Auswirkung auf die Spin-Bahn-Wechselwirkung studieren, die wir indirekt mit Methoden der ferromagnetischen Resonanz messen können.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Lin Chen
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Messung der Dopplerverbreiterung der Positronenannihilationslinie zur Charakterisierung von Dünnschichtsystemen |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Die Doppler-Verbreiterungsspektroskopie der Positronenannihilationsline (DBS) mit einem monoenergetischen Positronenstrahl ist eine hochsensitive Methode zur Charakterisierung von Gitterdefekten in oberflächennahen Schichten. Da verschiedene Materialien unterschiedliche Positronenaffinitäten aufweisen, lässt sich durch geschickte Kombination eine Grenzfläche herstellen, welche Positronen bevorzugt in eine Richtung passieren. Ziel der Bachelorarbeit ist es, eine Reihe solcher Dünnschichtsysteme mit DBS zu vermessen um deren Defektkonzentration und Güte zu bestimmen, sowie mit den gewonnen Daten das Auswerteprogramm LIMPID (Layer-wise Investigation of Measurements on Positron Implantation and Diffusion) zu verifizieren. Neben den DBS Messungen ist im Rahmen einer Kooperation mit der Arbeitsgruppe Plasma-Material-Wechselwirkung am MPI für Plasmaphysik geplant, Rutherford-Rückstreuspektrometrie (RBS) zur (destruktiven) Bestimmung der Schichtdicken einzusetzen.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Messung der ferromagnetischen Resonanz in senkrechter Geometrie an Ferromagnet/Topologischer Isolator Bi-Lagen |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- In diesem Projekt sollen temperaturabhängige Messungen der ferromagnetischen Resonanz an Ferromagnet/Topologischen Isolator Heterostrukturen durchgeführt werden. Als Funktion der Temperatur sollte es möglich sein den Anstieg der Linienbreite zu beobachten, der durch die Dominanz der topologischen Oberflächenzustände bei tiefen Temperaturen hervorgerufen wird.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Laura Pietanesi
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Modelling single photon sources for optical quantum circuits |
Poot |
- Arbeitsgruppe
- Quantentechnologien
- Beschreibung
For quantum technology it is very important to have sources for single photons. One of the techniques that can be used to create these, is called spontaneous parametric down conversion, or SPDC for short. Here photons with a high frequency can split into two daughter photons with about half the frequency. An important point in this technique is so-called phase matching: the low and high frequency photons should travel at the same speed through the nonlinear material. This is often achieved by using special crystals that have to be oriented carefully. For applications we want to integrated these sources on photonic chips. In this project we will expore the phase matching in waveguides using photonic simulations of waveguides.
- Forschungsfeld
- Nanostrukturen (Theorie) (~50%)
- Optik (Theorie) (~50%)
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Modern Computing Algorithms for Physics |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
The MPI offers a bachelor thesis in the field of modern computing, either connected with the BAT, Bayesian Analysis Tool, or the SSD, Solid State Detectors, open source program packages. Both packages are written in the innovative language JULIA. In either case a contribution to the package is expected as a well as a small application.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Nanodosimetrie für die Ionentherpie (Thema ist bereits vergeben) |
Wilkens |
- Arbeitsgruppe
- Professur für Medizinische Strahlenphysik (Prof. Wilkens)
- Beschreibung
- Radiation therapy for cancer patients with ions (for example carbon ions) is biologically more effective compared to conventional therapy with photons. However, reasons for the higher effectiveness are not yet fully understood. Nanodosimetry is a promising technique for discovering the underlying mechanisms of the higher potential to kill tumor cells.
Nanodosimetry counts ionizations in volumes of the size of a DNA segment. The distribution of ionization cluster sizes might explain the occurrence of DNA damage and contribute to the understanding of biological effectiveness.
In the case of carbon ion therapy, several fragments are present and cells are exposed to a mixed radiation field. Therefore, the nanodosimetric track structure characteristics have to be determined for each fragment species.
In this work, you will simulate nanodosimetric data for different particle types with a track structure code (TOPAS) and analyze the results in MATLAB.
Contact: Frauke Alexander, frauke.alexander@tum.de, 089-4140-9428
- Forschungsfeld
- interdisziplinäre Themen (Theorie)
- Betreuer(innen)
- Frauke Alexander
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Non-linear anomalous thermal transport in 2D materials with broken symmetry |
Holleitner |
- Arbeitsgruppe
- Nanotechnologie und Nanomaterialien
- Beschreibung
- In atomistic crystals with a broken inversion symmetry, a thermal gradient is supposed to generate a non-equilibrium spin-population at the edges of the material. So far, similar non-linear effects with an anomalous spin-population have been detected mainly by electronic means. This project explores the important impact of the thermal (phonon) bath on the spin-dynamics in corresponding crystals.
Interest or good knowledge in solid state physics, semiconductor physics, Python programming, optoelectronics or nanofabrication is a plus, but certainly not a must.
- Forschungsfeld
- Festkörperphysik (experimentell) (~40%)
- Nanostrukturen (experimentell) (~30%)
- Materialphysik (experimentell) (~30%)
- Betreuer(innen)
- Christoph Kastl
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Numerik für Neutronenoptik |
Wuttke |
- Arbeitsgruppe
- Jülich Center for Neutron Science
- Beschreibung
- In a collaboration between numerical mathematics and physics, we recently developed a new method to compute the reflectivity of thick mosaic crystals [1]. This method shall now be applied to a stack of rotating crystals so that it can be used for the optimization of the backscattering spectrometer [2] at the neutron source FRM 2. In the course of this thesis you will (a) extend the theoretical formalism, (b) add your extensions to extant C++ code, (c) run, analyze, and document exemplary simulations.
[1] https://doi.org/10.1107/S2053273320002065
[2] http://doi.org/10.1063/1.4732806
- Forschungsfeld
- Optik (Theorie)
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Open Quantum System, Linblad equation and decoherence in Quantum Mechanics |
Brambilla |
- Arbeitsgruppe
- Theoretische Teilchen- und Kernphysik
- Beschreibung
- We will study a two levels atomic system in an external electromagnetic field
using open quantum system and obtaining a master equation of
the Linblad type. We will solve the equation and compare to the results of
time dependent perturbation theory. We will use these results to study
Lindblad Decoherence in Atomic Clocks
(Steve Weinberg Phys. Rev. A 94, 042117 (2016).
Such results can be generalized to considering in the same framework a
chromoelectric dipole interaction between quarkonium color
octet and singlet states in QCD, the theory of strong interaction and can
describe the nonequilibrium evolution of quarkonium in heavy ion collsions
at experiments at the Large Hadron Collider at CERN.
Prerequisites: Quantum Mechanics I and II
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Lin Dai
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Optical pulser system for detector calibration |
Märkisch |
- Arbeitsgruppe
- Elementarteilchenphysik bei niedrigen Energien
- Beschreibung
- 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.
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, with the pulser system be put into operation, the communication with the system will be programmed and the system properties of it will be characterized in the laboratory.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Karina Bernert
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Optimal digital processing of the LEGEND-200 liquid argon instrumentation signals |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- The LEGEND project (https://legend-exp.org) aims at testing the fundamental laws of nature by searching for neutrinoless double-beta decay. A fundamental part of the experimental setup is composed by a liquid argon cryostat, instrumented with optical light sensors in order to suppress unwanted background events.
TUM has a leading role in developing and deploying the LEGEND-200 liquid argon instrumentation, composed of light-guiding fibers coupled to silicon photomultiplier (SiPM) light sensors. Data recorded by these devices are analyzed to search for signals above noise ( due to, for example, a nearby radioactive decay), and discard them as background. The signal searched by LEGEND, neutrinoless double beta decay, is not accompanied by emission of light in liquid argon.
The thesis project consists in analyzing early SiPM data collected during tests of the LEGEND-200 instrumentation at the Laboratori Nazionali del Gran Sasso in Italy at the end of 2021. In particular, the candidate is expected to develop optimal Digital Signal Processing (DPS) algorithms to estimate parameters like energy and timing of the recorded traces. The result of these studies are critical to evaluate the performance of the experimental setup and determine the best data analysis strategy.
The candidate will learn to use the existing software tools to analyze digital signals. Notions of Python programming are beneficial. The candidate will acquire skills in developing DSP routines in Python, including popular tools in the scientific computing community (e.g. NumPy, HDF5 file format), and work on remote high-performance computing facilities.
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 Dr. Luigi Pertoldi. Please contact schoenert@ph.tum.de or luigi.pertoldi@tum.de for further information.
We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Teilchen und Felder (experimentell) (~50%)
- Kernphysik (experimentell) (~20%)
- Astrophysik (experimentell) (~30%)
- Betreuer(innen)
- Andreas Leonhardt
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Orientierungsabhängigkeit der Photoemissionszeit kleiner Iodalkane (Thema ist bereits vergeben) |
Kienberger |
- Arbeitsgruppe
- Laser- und Röntgenphysik
- Beschreibung
In dieser Bachelorarbeit wird die Abhängigkeit der I4d-Photoemissionszeit von der orientierung des Moleküls zur Zeit der Photoionisation mittels numerischer Methoden studiert. Es ist eine brandheiße Fragestellung in der Ultrakurzzeitphysik, bei der geklärt werden soll, wie viele Attosekunden Verzögerung durch die Migration eines Elektrons durch ein Molekül entsteht. In this thesis the dependency of the I4d photoemission time delay on the molecular orientation at the time of photoionization is studied via numerical methods.
- Forschungsfeld
- Quantenoptik (experimentell)
- Betreuer(innen)
- Christian Schröder
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Pattern Formation via Local Cell-Cell Signaling with Variable Interaction Ranges |
Gerland |
- Arbeitsgruppe
- Theorie komplexer Biosysteme
- Beschreibung
Pattern formation phenomena occur in many different contexts ranging from physical and chemical systems to developmental biology and synthetic biology. In developmental biology, the correct relative positioning and determination of different cell fates is essential to ensure that the organism functions correctly. Whilst many models for pattern formation exist, the focus here is on cellularized systems with interactions only between nearby cells. This form of communication has previously received less attention from theoretical research than e.g. long-range diffusible signals as a means of communication. Our goal is to explore fundamental limits, patterning concepts, and engineering potential with a simple top-down model. Building on previous work, the project will concentrate on searching mechanisms of pattern formation with the goal of investigating how the interaction range can influence the ability to realiably create paradigmic patterns like striped "French Flag" patterns with tunable widths of the stripes. Prior knowledge in biology/biophysics is not needed, but interest in theoretical physics and computational problem solving is expected.
- Forschungsfeld
- Biologische Physik (Theorie) (~60%)
- interdisziplinäre Themen (Theorie) (~40%)
- Betreuer(innen)
- Stephan Kremser
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Performance of electronics for precision beta spectroscopy (Thema ist bereits vergeben) |
Märkisch |
- Arbeitsgruppe
- Elementarteilchenphysik bei niedrigen Energien
- Beschreibung
- The instrument PERC is currently under construction at the FRM II and will investigate correlations in the weak decay of the neutron with highest precision in order to test the Standard Model of particle physics.
For this experiment, we develop a new silicon detector for precision spectroscopy of electrons from neutron decay. A multi-channel-analyzer (MCA) collects its data. In our case, this device includes a small amplifier, an analog-digital-converter and an FPGA for the data analysis. Like any electronic device, the MCA is not perfectly linear and also crosstalk can occur between the different channels.
Within this thesis, the properties of the MCA will be characterized in detail with the help of an arbitrary waveform generator. Results will be used to test the performance of development samples of the silicon detector. (Thesis in German or English).
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Manuel Lebert
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Perovskite solar cells for space applications |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
-
Perovskite solar cells have become a hot research topic in the last few years. The lightweight thin-film solar cells are of particular interest for space applications due to their exceptional power per mass, exceeding their inorganic counterparts by magnitudes. Presently, the next space study of perovskite solar cells is under preparation. Thus, the task will be to build perovskite solar cells on flexible substrates and characterize them under terrestrial condition to identify interesting candidates, which can be selected for a future space mission. Main characterization will be IV-curve measurements and EQE studies.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Printed perovskite solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- 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.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Printed ZnO films |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- ZnO nanostructures with tunable optical, electrical properties can enable the realization of high-efficient nanodevices such as gas sensors, solar cells, light-emitting diodes and energy harvesters. Due to the rich phase separation behavior of block copolymers, they serve as the soft template to construct ZnO architectures with different morphologies and physical properties. Towards large-scale fabrication, an industrial-based slot-die printing technique is used as the film formation method. In this work, the morphology tuning of mesoporous ZnO thin films based on the slot-die coating and self-assembly pathway during the film formation process will be investigated and correlated with optical properties of the printed ZnO films.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Quantenmechanische Berechnung molekularer Raman Spektren |
Egger |
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Quantentransport in ferromagnetischen, austauschgekoppelten supraleitenden Nanodrähten |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- Wir werden Thullium Yttrium Garnet (TIG)/Supraleiter-Heterostrukturen untersuchen, um den Einfluss des Supraleiters auf die Magnetisierungsdynamik über ferromagnetische Resonanz zu erforschen. Da TIG eine senkrechte magnetische Anisotropie aufweist, wäre es interessant, den Transport im Supraleiter durch Messungen wie die I-U-Charakterisierung eines auf TIG hergestellten SQUID zu untersuchen und die Flussquantisierung im SQUID als Funktion der Magnetisierung des TIG zu quantifizieren.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Dhavala Suri
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Quarkonium at non-zero isospin density |
Brambilla |
- Arbeitsgruppe
- Theoretische Teilchen- und Kernphysik
- Beschreibung
- We study the change of quarkonium bound states energies in the presence
of a medium of nonzero isospin density using results from Lattice QCD and Effective field theories and solving the Schroedinger equation with the corresponding potentials.
We will investigate how the medium induces a reduction of the quarkonium energies and if the reduction of the quarkonium energies becomes more pronounced as the
heavy-quark mass is decreased, similar to the behaviour seen in two-colour QCD at non-zero quark chemical potential. In the process of our analysis, we will study the eta_b-pi and Upsilon-π scattering phase shifts are determined at low momentum.
These findings are relevant for experiments at FAIR in Fermany and at the
future Electron Ion Collider in US.
Prerequisites: Quantum Mechanics I and II
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Xiangpeng Wang
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Quell- und Gelierverhalten dünner Filme aus pH-responsiven telechelischen Blockcopolymeren (Thema ist bereits vergeben) |
Papadakis |
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Reaction-diffusion simulations of the influence of surface processes on hydrogen release from tungsten |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
Hydrogen isotope retention in plasma-facing components in fusion devices is an issue from the safety and economic points of view. Its predictions are often based on reaction-diffusion simulations. The simulations require the parameters describing hydrogen interactions with the material. These parameters are frequently obtained from simulations of laboratory experiments, in particular, desorption spectroscopy (TDS). In the simulation of TDS results it is often assumed that the result is governed by bulk processes, while processes at the material surface are very fast. Alternatively, very simplified models of surface processes are used. Within this bachelor thesis, the student will perform reaction-diffusion simulations utilizing a more rigorous model of hydrogen interaction with metal surfaces. By performing systematic parameter studies, the effects of surface processes on TDS results will be elucidated.
Contact: Dr. Mikhail Zibrov
- Forschungsfeld
- Plasmaphysik (experimentell)
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Refinement of protein-peptide complexes using replica exchange with repulsive scaling |
Zacharias |
- Arbeitsgruppe
- Molekulardynamik
- Beschreibung
- The protein-peptide binding plays a major role for many cellular processes. The prediction how peptides interact with partner proteins is still an unsolved problem. In this BSc thesis a new method for improved sampling in Molecular Dynamics simulations will be used and tested on predicting the structure of protein-peptide complexes. The thesis gives important insights into molecular interactions but also in computer simulation methododologies.
- Forschungsfeld
- Biologische Physik (Theorie)
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Röntgen Phasenkontrast Bildgebung an hoch brillianten Quellen (Thema ist bereits vergeben) |
Herzen |
- Arbeitsgruppe
- Physik der biomedizinischen Bildgebung
- Beschreibung
- In this project phase-contrast imaging techniques are used at a synchrotron source. Utilizing the high brilliance and coherence of PETRA III, phase-contrast imaging can improve soft tissue visualization and is among the standard imaging techniques of imaging setups. We build and operate a phase-contrast imaging setup at the beamlines P05 and P07 at PETRA III (DESY, Hamburg) in cooperation with the Helmholtz-Zentrum Hereon. This project will mainly deal with data analysis for different applications, but you will also have the chance to join one of the beamtimes at the setups in Hamburg, as well as learn more about the state-of-the-art phase-contrast imaging. Basic programming skills in Python would be beneficial.
- Forschungsfeld
- interdisziplinäre Themen (experimentell)
- Betreuer(innen)
- Nelly de Leiris
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Simulation and comparison of non-planar qubit architectures |
Filipp |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Scalable designs of superconducting qubits are essential for the creation of large-scale multi-qubit processors used in quantum computers. Superconducting transmon qubits are described by their characteristic capacitance and the critical current of their Josephson-Junction. The capacitance of these qubits orginates from the geometry of the metal islands of the qubit on the chip surface. To accomodate for a large number of qubits and their respective control and readout lines new 3D integration methods have been developed over the last years, extending the superconducting structures beyond a single chip plane. In this work a number of these architectures will be simulated. The focus of this Bachelor thesis lies in the accurate simulation
of these designs ranging over different orders of magnitude in size and the extraction of system paramerters from FEM solutions.
- Forschungsfeld
- Festkörperphysik (experimentell) (~20%)
- Festkörperphysik (Theorie) (~30%)
- Quantenoptik (experimentell) (~20%)
- Quantenoptik (Theorie) (~30%)
- Betreuer(innen)
- Ivan Tsitsilin
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Simulation of optical photons in the LEGEND-200 liquid argon |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- The LEGEND project (https://legend-exp.org) aims at testing the fundamental laws of nature by searching for neutrinoless double-beta decay. A fundamental part of the experimental setup is composed by a liquid argon cryostat, instrumented with optical light sensors in order to suppress unwanted background events.
Starting from February 2022, the LEGEND group at TUM is looking for a student to study the performance of the liquid argon detector. The thesis project consists in a simulation of optical photon propagation and detection in liquid argon from within the LEGEND-200 cryostat. The candidate will develop a software package, based on existing Monte Carlo simulation tools, that reproduces the experimental setup in terms of dimensions, material (optical) properties and light sensors. The results of this simulation will be benchmarked against physics data acquired with radioactive sources during tests of the LEGEND-200 instrumentation at the Laboratori Nazionali del Gran Sasso in Italy at the end of 2021.
Notions of Python and C++ programming are beneficial. The candidate will learn how to develop an application based on the particle tracking software GEANT4 (https://geant4.web.cern.ch), and will have the possibility to run it on a remote high-performance computing facility. The acquired skills include processing of the simulation output to extract physical quantities of interest. An additional, optional work package for the motivated candidate, would be to investigate the possibility to perform a significantly more efficient simulation on graphic cards (GPUs), by exploiting their ray-tracing capabilities.
Supervision at the Physics Deptartment by Prof. Schönert and Dr. Luigi Pertoldi. Please contact schoenert@ph.tum.de or luigi.pertoldi@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Luigi Pertoldi
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Simulation von "Elastic Recoil Detection"-Analysen (ERDA) auf rauen Oberflächen |
Stroth |
- Arbeitsgruppe
- Plasmarand- und Divertorphysik
- Beschreibung
Elastic Recoil Detection Analysis (ERDA) ist eine Ionenstrahlanalysemethode mit einfallenden Ionen im Energiebereich von einigen 10 MeV. Die Methode wird weltweit häufig zur quantitativen Analyse der Zusammensetzung von Festkörperoberflächen genutzt. Während ERDA für glatte Oberflächen gut funktioniert, ist allerdings schon länger bekannt, dass die Methode durch Oberflächenrauigkeit gestört werden kann. Das Ausmaß dieser Störung und der Einfluss auf die Quantifizierbarkeit von ERDA wurden aber nur ansatzweise untersucht und hängen letztlich wohl auch von der Art der Rauigkeit ab. Im Rahmen dieser Arbeit soll mit Hilfe von Simulationsrechnungen unter Benützung der Structnra/Simnra Software der Einfluss verschiedener Arten von künstlichen und realen Oberflächenrauigkeiten auf ERDA Energiespektren sowie die daraus abgeleiteten elementaren Zusammensetzungen und Tiefenprofile untersucht werden.
Contact: Dr. Matej Mayer
- Forschungsfeld
- Plasmaphysik (experimentell)
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Spektrale Röntgen Dunkelfeld Bildgebung (Thema ist bereits vergeben) |
Herzen |
- Arbeitsgruppe
- Physik der biomedizinischen Bildgebung
- Beschreibung
- The aim of this project is to combine spectral X-ray imaging and dark-field imaging. Spectral X-ray imaging is a highly emerging technique. By imaging an object with two or more different photon spectra, the energy-dependent attenuation is retrieved, which allows for a quantitative and material-selective analysis of the sample. Technically this can be realized by photon-counting detectors, which are able to resolve single photons regarding their energy.
Novel X-ray dark-field imaging with a grating interferometer exploits small-angle scattering of X-rays and thus provides information about the microstructure of the sample. Comparable to the energy-dependent attenuation of different materials, the dark-field signal varies for different microstructures and X-ray energies. The long-term aim is to transfer imaging analysis techniques known from the attenuation contrast channel to the dark-field channel.
The student project mainly focuses on experimental validation of underlying concepts at a stationary laboratory CT setup, as well as the demonstration of potential applications of spectral X-ray dark-field imaging.
This thesis will be split up in 50% experimental work in the laboratory and 50% algorithmic development and data processing.
- Forschungsfeld
- interdisziplinäre Themen (experimentell)
- Betreuer(innen)
- Kirsten Taphorn
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Spin-Hall-Effekt/Spin-Transfer-Torque-induzierte Kontrolle der Anregung/Ausbreitung von Spinwellen (Thema ist bereits vergeben) |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- Spinwellen können durch Injektion von Spindrehimpuls angeregt werden. Dies kann durch den sogenannten Spin Hall Effekt (SHE) realisiert werden. Außerdem sollte es möglich sein die Ausbreitung von Spinwellen durch den SHE bzw. den Spin Transfer Torque zu steuern. Wie verwenden zeit- und ortsaufgelöste magnetische Mikroskopie um die Spinwellenausbreitung zu detektieren.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Christian Riedel
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Spinwellenausbreitung in Bi-YIG |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- Spinwellenspektroskopie (elektrisch und optisch) und SQUID-Messungen sollen an ferrimagnetischen Bi-YIG Filmen durchgeführt werden, um die Eigenschaften der Filme in Bezug auf die Spindynamik zu charakterisieren. Wenn es die Zeit erlaubt, werden wir die Leistungsabhängigkeit spezifischer Spinwellen-Anregungen (MSBVW) untersuchen und die Beziehung zwischen kohärenten Spinwellen und Bose-Einstein-Magnonen (oder Magnonen bei der niedrigsten Energie) untersuchen.
- Forschungsfeld
- Festkörperphysik (experimentell)
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Storing memories in vascular architecture |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Arteries making up our vasculature are dynamics and continuously change their diameters in response to the flows pervading them. In fact, those changes allow the vasculature to store memories about flows in the past. Yet, on which time scales are memories made and forgotten? You will numerically simulate memory formation in a model of adaptive networks. Numerically probing for memories at different time intervals you will determine the physical parameters that govern how long it takes to form a memory and when memories are forgotten. You will learn about statistical physics of disordered systems, Matlab. Prerequisite: Good memory :)
Task 1 Implement local artery dynamics into our Matlab code
Task 2 Numerically write and probe memory formation while varying model parameters
Task 3 Derive scaling relation on how model parameters determine the time scales of memory formation and loss.
- Forschungsfeld
- Biologische Physik (Theorie) (~50%)
- interdisziplinäre Themen (Theorie) (~50%)
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Strukturbildung im Zytoskelett |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Beschreibung
- Biologie hat die einzigartige Fähigkeit Strukturen mit faszinierender Komplexität zu bauen. Zugrundeliegen sind Selbstorganisationsphänomene - allein durch die Wechselwirkung von verschiedenen Bausteinen enstehen Strukturen mit einer Funktion. Die drunterliegenden Physik zu verstehen benötigt Modellsysteme, die einfach genug, jedoch gleichzeitig komplex genug sind, die Prinzipien verstehen zu können. Im Rahmen der Arbeit sollen die Strukturbildung im Zytoskelett untersucht werden. Dazu kommen verschiedene hochauflösende Mikroskopiemethoden und digitale Bildverabeitungsansätze zum Einsatz.
- Forschungsfeld
- Biologische Physik (experimentell)
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Superlattice deformation in quantum dot films and its impact on optoelectronic performance |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
-
Quantum dots (QDs) nowadays find a broad application, ranging from TV screens to next- generation solar cells. Like artificial atoms, QDs form a superlattice structure when prepared as a thin film. This project aims to investigate the impact of deformed superlattices on optoelectronic performance. You have the chance to prepare QD films on stretchable substrates and introduce superlattice deformation by stretching in a custom-built apparatus. At the same time, you will trace the introduced optoelectronic changes with photoluminescence measurements and UV-Vis spectroscopy to deepen the understanding of this fascinating quantum material.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Synthesis and self-assembly of gold nanoparticles for optoelectronic devices |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- 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.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
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Test neuer Myondetektoren fuer das ATLAS-Experiment am Large Hadron Collider |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Fuer den Betrieb des ATLAS-Experiments bei sehr hohen Proton-Kollisionsraten am Large Hadron Collider (High-Luminosity LHC) werden neue schnelle und strahlungsbestaendige Myondetektoren gebaut. Die Eigenschaften dieser Detektoren sollen im Rahmen der Arbeit systematisch getestet werden.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Test neuer schneller Ausleselektronik fuer das ATLAS-Experiment am Large Hadron Collider |
Kroha |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- Fuer den Betrieb des ATLAS-Detektors bei sehr hohen Proton-Kollisionsraten am Large Hadron Collider (High-Luminosity LHC)wird neue schnelle Ausleseeletronik in Form von integrierten Schaltkreisen (Mikrochips)fuer die Myondetektoren entwickelt.
Die ersten Versionen der neuen Chipssollen im Rahmen der Arbeit getestet werden.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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Test of Gemanium Detectors |
Caldwell |
- Arbeitsgruppe
- Max-Planck-Institut für Physik / Werner-Heisenberg-Institut (MPP)
- Beschreibung
- The MPI offers a bachelor thesis in the field of germanium
detector technology. The MPI operates a number of test stands.
The successful candidate will conduct some measurements
with novel germanium detectors and perform a first analysis
with respect to detector R&D.
- Forschungsfeld
- Teilchen und Felder (experimentell)
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The Cosmic Neutrino Background (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
Neutrinos are the most elusive among the known particles. At the same, time neutrinos are expected to be ubiquitous in our Universe. Concretely, it is expected that our Universe contains about 300 neutrinos per cm3, which are relics of processes occurring in the very early stages of the cosmic history. The aim of this thesis will be to study the formation of the Cosmic Neutrino Background (CNB) in the process of neutrino decoupling, and to study the time evolution of the neutrino contribution to the energy density of the Universe from the formation of the CNB until today. The thesis will also address the possible influence of the cosmic neutrinos on Big Bang Nucleosynthesis and on the Cosmic Microwave Background.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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The Hubble Tension (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
The Universe appears to be expanding faster than expected within the standard cosmological model. The expansion rate of the Universe today is parametrized by the Hubble constant and local observations point to values of the Hubble constant that are significantly larger than those predicted by the standard cosmological model that explains an array of cosmological observations, including the CMB, BBN and the distribution of the large scale structures of the Universe. This situation goes by the name of the Hubble tension and is dominating the cosmological conversation today.
The aim of this project will be to study this timely issue. In particular, the student will 1) review the various methods used to measure the Hubble constant, 2) study the expansion history of the Universe and study how the Hubble constant is predicted given a cosmological model. If time allows, the student could also explore some extensions of the standard cosmological model that can account for a faster expansion of the Universe today.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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The Hunt for the Rarest Cosmogenic Nuclei |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- As you have probably seen many times in various calculations in special relativity, a large amount of muons are produced in the atmosphere in so-called particle showers. These incredibly fast muons can reach the Earth's surface and even penetrate it to some degree.
This is a problem because most low background experiments want to avoid having these muons corrupt their data. Therefore, many experiments are conducted in underground laboratories. Yet they cannot completely avoid their influence. A large part of the background caused by atmospheric muons can be removed by so-called muon vetoes, which check whether the signal in the detector matches a particle coming from outside. However, the muons can still cause some background in the form of cosmogenic radioactive nuclei. These are produced during high-energy muon crossings through the detector and can decay with a significant delay to the muon crossing which makes it hard to veto them.
This is the case for LEGEND-1000 (https://legend-exp.org), an experiment planned to look for neutrinoless double beta decay. To estimate the impact of specific isotopes on the final data we use Monte-Carlo simulations. These simulate how a muon will interact with the detector and which nuclei will be produced.
The student's task will be to perform simulations to estimate the production rate of certain cosmogenic nuclei and their possible impact on the final experiment. In doing so, they will learn about the processes by which cosmogenic nucleons are produced, what signal their decay will leave in the detectors, and what strategies one has to filter them out. The work will involve using C++ to modify the simulation and ROOT to analyze the results. A basic understanding in these would be beneficial but not necessary.
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 Moritz Neuberger Please contact schoenert@ph.tum.de or Moritz.Neuberger@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Moritz Neuberger
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The neutrino floor for direct dark matter searches (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
The Earth is being constantly bombarded by dark matter particles from outer space. The dark matter particle could interact with the protons and neutrons of a target in a dedicated detector, thus providing evidence for the particle nature of the dark matter. This search strategy, dubbed direct detection, requires an exquisite shielding of the target material against cosmic rays, nuclear decays and many other processes that can mimic a dark matter signal. However, neutrinos from the Sun or the atmosphere cannot be shielded, thus producing an irreducible background for direct dark matter searches; this is the so-called "neutrino floor". The aim of this thesis is to calculate the neutrino floor generated in the coherent elastic scattering of solar or atmospheric neutrinos off some commonly used target materials.
- Forschungsfeld
- Teilchen und Felder (Theorie)
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Theoretische Untersuchungen von dynamischen Verzerrungen in Materialien |
Egger |
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The P+ spoiler: from minerals to alpha-decay tagging |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- In the last decade, experiments searching for neutrinoless double-beta decay of 76Ge provided the most stringent limits on the half-life of the process. This was possible thanks to the careful choice of clean materials and very efficient background reduction techniques. The combination of the two allowed to simplify the search for neutrinoless double-beta decay into the search for an energy peak on a null background.
This work will focus on one source of background, which is the alpha-decays of radioactive contaminants on the surface of germanium detectors. Such a contamination can occur when detectors are exposed to air, thus Radon, which can deposit its radioactive progeny on their surface. The tagging of these alpha events with small anode detectors has proved to be very efficient; indeed, no events in the alpha peak have survived the analysis cuts in the full dataset of the GERDA experiment, and only a limit for the tagging efficiency has been extracted.
In view of the future LEGEND experiment, the “p+ spoiler” setup was designed to build a high statistics sample of alpha decays on the surface of germanium detectors and extract the central value of their tagging efficiency. This is done by exposing detectors to an Autunite mineral, which, containing Uranium, works as a constant Radon emanator.
In this thesis, the student will work on the data acquired from a germanium detector which has been “spoiled” for several months. They will be guided to the analysis of its data and to the final extraction of the tagging efficiency of alpha-decays. A background in programming in C/C++ is welcome, but not mandatory.
The theses will be carried out at the Chair for astroparticle physics of the Physics Department. Supervision at the Physics Department by Prof. Schönert and Tommaso Commelato. Please contact schoenert@ph.tum.de or tommaso.comellato@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Tommaso Comellato
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Ungeordnete Quantensysteme: Vielteilchenlokalisierung |
Knap |
- Arbeitsgruppe
- Kollektive Quantendynamik
- Beschreibung
Disorder has a drastic influence on transport properties. In the presence of a random potential, a system of electrons can become insulating; a phenomenon known as many-body localization (MBL) that has been envisioned by the Nobel laureate Phil Anderson. However, even beyond the vanishing transport such systems have very intriguing properties. For example, many-body localization describes an exotic state of matter, in which fundamental concepts of statistical mechanics break down. In this project we will explore these exciting aspects of many-body localization.
- Forschungsfeld
- Festkörperphysik (Theorie) (~80%)
- Quantenoptik (Theorie) (~20%)
- Betreuer(innen)
- Michael Knap
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Untersuchungen zur elektronischen Lokalisierung in Energie-Materialien |
Egger |
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Untersuchung verschiedener Transient-Klassen mittels Fermi/GBM Daten |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- 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
- Forschungsfeld
- Astrophysik (experimentell)
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Vielteilchensysteme mit Zwangsbedingungen |
Knap |
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Vortizes mit grosser topologischer Ladung (Thema ist bereits vergeben) |
Beneke |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
- Topologically non-trivial vortex solutions of classical field
equations are relevant to various areas of physics: superfluidity,
confinement of the charge of the strong interaction, perhaps
in cosmology. While the existence of the solution can easily
be shown, there is often no explicit analytic solution known.
After working out the basic theoretical concepts (homotopy
theory, classical gauge field theory), the results of recent
papers should be reproduced and generalized, which construct
analytic solutions for large topological charge n of the vortex
by using asymptotic expansions in 1/sqrt{n}.
- Forschungsfeld
- Teilchen und Felder (Theorie)
- Betreuer(innen)
- Jan-Niklas Toelstede
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Wechselwirkung zwischen Spin-Orbit-Torque und supraleitenden Zuständen in Ni/Bi Heterostrukturen |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- Durch Magneto-Transport Messungen bei tiefen Temperaturen können sogenannte Spin-Orbit-Torques detektiert werden, die ausgenutzt werden können um die Magnetisierung von dünnen Filmen zu manipulieren. In diesem Projekt sollen Kombinationen aus ferromagnetischen Schichten und Supraleitern untersucht werden.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Lin Chen
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Wie Adern wachsen und sich anpassen |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Unser Adernetzwerk ist wichtig um Sauerstoff und andere wichtige Ressourcen in unserem Körper zu transportieren. Dabei ist unser Adernetzwerk nicht statisch sonder passt sich in seiner Struktur, in der Dicke einzelner Adern fortwährend an. Welche Gesetzmäßigkeiten folgt die Dynamik einzelner Adern? Welche Rolle spielt dabei die Strömung in den Adern? Du wirst Daten von Adernetzwerken auf einem Mikrofluidik Chip analysieren, um die Dynamik der Adern quantitativ zu erfassen. Dazu entwickelst Du Bildanalyseverfahren weiter und passt sich auf unsere ganz neuen Daten von Adern an.
- Forschungsfeld
- Biologische Physik (experimentell) (~20%)
- Biologische Physik (Theorie) (~80%)
- Betreuer(innen)
- Fatemeh Mirzapour
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Xenon doped liquid argon - mixing, measuring, modeling |
Schönert |
- Arbeitsgruppe
- Experimentelle Astroteilchenphysik
- Beschreibung
- At the first glance, liquid argon as a detector material might seem to be a peculiar choice: its low boiling point of 87 K makes it difficult to handle and puts hard constraints on any material touching it. Nonetheless, many experiments in the field of astroparticle physics employ it as a detection medium - from dark matter search to neutrinoless double beta decay. This is due to its superior properties as a scintillation medium. Via the scintillation process, energy depositions (e.g. from a dark matter particle scattering off a nucleus or gamma particles interacting) lead to light emission in the liquid argon volume. A high light output is key for a good energy reconstruction, as exhibited by liquid argon.
Current efforts are made in doping liquid argon with small traces of Xenon (at parts-per-million levels), in order to further enhance the light output. Properties like the time spectrum and total light output of the light emitted by this noble gas mixture are not sufficiently understood as of now.
Measurement runs in a 1m³ liquid argon cryostat located in a shallow underground lab at TUM are conducted to study these effects at various Xenon concentrations. An optical detection and monitoring system (LLAMA) is used to obtain time-resolved optical properties.
The Bachelor candidate works on the modeling of the light emission process of this Xe-Ar-mixture using data obtained so far. Furthermore, they will take part in setting up, conducting and analyzing data obtained in a new measurement run planned to commence in June 2022.
As the work includes the fitting of data present in ROOT format, basic C++ skills are beneficial, but not required. Skills in programming, data analysis and modeling are acquired by the student, in addition to knowledge in the handling of gas and cryogenic liquids by hands-on laboratory work.
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 Mario Schwarz. Please contact schoenert@ph.tum.de or Mario.Schwarz@tum.de for further information. We will organize a dedicated meeting for interested students on Tuesday, February 1, 14:00-16:00. For more information please check https://www.moodle.tum.de/course/view.php?id=75320
- Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~40%)
- Kernphysik (experimentell) (~30%)
- Betreuer(innen)
- Mario Schwarz
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