|
|
2D optomechanics (Thema ist bereits vergeben) |
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%)
|
|
|
3D Druck von Herzmuskelgewebe |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Beschreibung
- In diesem Projekt sollen Bioprinting Methoden entwickelt werden, die es ermöglichen Herzmuskelzellen in ein funktionierendes Gewebe zu organisieren. Dazu werden menschliche IPS Zellen zu Herzmuskeln differenziert, und die Selbstorganisationsprozesse der Zelldifferenzierung untersucht. Die Kontraktionen des Gewebes sollen dann verwendet werden, um die Effizienz des Protokolls zu quantifizieren. Ultimative Ziel ist es mit dem zu entwickelnden Assay eine Plattformtechnologie für Wirkstoffforschung zu etablieren.
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
3D Mikroskopie, Visualisierung und geometrische Analyse von Organoiden mithilfe Machine Learning Algorithmen |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
Active response by adaptation of mechanical properties? |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- The complex behavior of the giant cell Physarum polycephalum finds its origin in the versatile transformation of liquid cytoplasm to gel-like actin-myosin meshwork making up the tube walls and vice versa. These active mechanics allow the organism to recycle its’ gel-like tubes at its rear and move it in its fluid form to the front, where it grows.
Also, responding to stimuli like food, touch, or light, a change in cytoplasm viscosity seems to initiate the response. Yet, what are the mechanical properties of the liquid cytoplasm, and how much do they change upon stimulation? Do the mechanical properties of the cytoplasm change with the location in the cell? The measure of the mechanical properties of cells is challenging, but one can probe their visco-elasticity by tracking injected micron-sized beads - a technique called microrheology. You will measure the mechanical properties of cytoplasm extracts and grown Physarum, and quantify how they change upon stimulation by passive and active microrheology.
Task 1: Establish cytoplasm extraction following previous work in the literature.
Task 2: Perform passive microrheology on cytoplasmic droplets without and with stimulation (light, food, drugs) and analyze your data quantitatively.
Task 3: Establish active microrheology to extract cytoplasm viscosity in different parts of Physarum’s network.
- Forschungsfeld
- Biologische Physik (Theorie) (~40%)
- Biologische Physik (experimentell) (~50%)
- Physik der weichen Materie (Theorie) (~10%)
- Physik der weichen Materie (experimentell) (~00%)
|
|
|
Air degradation process of green-solvent based organic solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
Organic solar cells are exciting since they can be flexible, light-weight and potentially cheap. Non-fullerene organic solar cells have gained great attention in recent years due to their increasing performance and stability, while the inevitable moisture and oxygen during production and operation would still cause degradation of the devices. Here, we select one high-efficiency green-solvent based organic solar cell and observe their degradation process in air under illumination. The device performance change as well as the degradation origin will be observed and analysed. Furthermore, the degradation mechanism under illumination in air is explored to help to find some improvement approaches. The device performance and stability are tested in air, the morphology of degraded layer is studied with imaging in real space and the crystallinity and molecular stacking is probed with X-ray scattering. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Anisotropic “breathing” of Li-ion batteries studied by optical micrometry |
Petry |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Despite their simple principle of operation, modern lithium-ion batteries are sophisticated electrochemical devices possessing different degrees of freedom. Along with typically used complex geometries (aimed to maximise volumetric and gravimetric energy/power density) make the interaction inside and the relationship between them quite complex. De-/intercalation of lithium in the layered structure of positive and negative electrodes leads to changes of the electrode stack dimensions, which results in changeexpansion/contraction of Li-ion batteries during cycling. The anisotropic changing of the diameter of cylindrical 18650-type Li-ion batteries was reported in the literature, which may has direct consequences on the integrity of the battery, the electrical contact between electrodes and thus on the cell performance. The aim of the current project is the monitoring of the cell dimension evolution using optical micrometry, the quantification of the degree of anisotropy vs. the battery state-of-charge and state-of-health. Systematics relating the degree of anisotropy and different types of Li-ion batteries will be created.
Common supervision is foreseen with Dr. Anatoliy Senyshyn, diffraction group leader at MLZ.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
- Betreuer(innen)
- Anatoliy Senyshyn
|
|
|
Automated Pre-Processing of Cell Culture Image Datasets for Machine Learning |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
Bestimmung der atomaren Leerstellenkonzentration in abgeschrecktem Wolfram durch Doppler-Verbreiterungsspektroskopie der Positronenannihilationslinie |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Doppler-broadening spectroscopy (DBS) of the positron annihilation line with a mono-energetic positron beam is a highly sensitive method to characterize lattice defects within the first few microns of a sample. The creation and behaviour of such defects in tungsten is of outmost interest in nuclear fusion research where tungsten is used as inner wall material of the plasma vessel withstanding the high particle flux and heat loads. A material close to its melting point contains a non-negligible thermal vacancy concentration which can be ’frozen in’ by cooling down a sample very fast from high temperature (quenching). The resulting vacancy concentration, however, is not homogeneously distributed as the mobility of vacancies depends heavily on temperature. The goal of this work is to verify experimentally the vacancy distribution calculated theoretically. Since the probing depth ( ≈ 1.5 µm) of DBS is smaller than the depth beyond which the defect concentration is expected to level out (a few 10 µm), multiple DBS measurements are required with intermittent removal of a surface layer (1 µm to 10 µm).
The sample preparation and the quenching procedure will be performed at the labs of the workgroup Ion Beam Analysis and Modification at the MPI for Plasma Physics. The project is carried out within the TUM research group Physics with Positrons.
- Forschungsfeld
- Festkörperphysik (experimentell) (~60%)
- interdisziplinäre Themen (experimentell) (~40%)
|
|
|
Bestimmung der Positroniumsbildung an Polymeroberflächen mithilfe eines Positronenstrahls |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
- Ziel der Bachelorarbeit ist es, die Bildung von Positronium über die 3-gamma-Annihilation an verschiedenen Polymeroberflächen zu beobachten. Hierzu verwenden wir einen monoenergetischen Positronenstrahl, der durch das Anlegen einer (Hoch-)Spannung auf die Probe beschleunigt wird. Die 3-gamma Annihilation lässt sich routinemäßig mit den vorhandenen Ge-Detektoren messen. Auf diese Weise lässt sich tiefenaufgelöst die Positroniumbildungsrate bestimmen.
Das Projekt wird in der TUM Forschungsgruppe Physik mit Positronen durchgeführt.
- Forschungsfeld
- Festkörperphysik (experimentell) (~80%)
- interdisziplinäre Themen (experimentell) (~20%)
|
|
|
Characterizing CsI coated THGEMs for photon detection |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- Traditional devices for photon detection like the Photomultiplier Tube or more recent technologies such as Silicon Photomultipliers are very cost-intensive. Therefore, especially with large area experiments in mind it is very interesting to investigate new ways of detecting photons.
In this project we are taking the approach of combining a photosensitive material with a Thick GEM (THGEM) in a gaseous detector. THGEMs are robust, low-cost devices, which can be used for electron multiplication. The THGEM is coated with a photosensitive material and placed within an electrical field. When a photon releases an electron from the material the photo electron drifts in the THGEM hole and undergoes avalanche amplification due to a high electric field that is preset inside the holes. Below the THGEM an anode is used for electron readout. Depending on the gain of the THGEM this could enable single photon detection.
In the scope of the thesis CsI coated THGEMs, which are useful in the UV light range, will be characterized and their quantum efficiency will be studied.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Thomas Klemenz
|
|
|
Charakterisierung nicht-depolarisierender Neutronspiegel |
Märkisch |
- Arbeitsgruppe
- Elementarteilchenphysik bei niedrigen Energien
- Beschreibung
- Among else, the PERC facility at the FRM II aims to determine the element V_ud of the CKM quark-mixing matrix from neutron betay decay with unprecedented precision. It will measure the parity-violating beta asymmetry similar to the seminal experiment by Wu and colleagues.
This requires prior knowledge of the polarisation of the neutron beam at the 0.1 permille level. A non-depolarising neutron guide contains the cold neutron beam inside the strong magnetic field of the 12m long superconducting magnet system of PERC. The guide consists of a novel layer system of copper and titanium.
Within this project, we will perform a measurement campaign at the Institut Laue-Langevin, Grenoble, France, to characterise the (de)polarisation properties of these neutron mirrors using two different techniques: off-specular reflection of a polarised beam and a custom setup using two state of the art polarised He3 spin-filter cells. You will participate in the preparation and execution of the campaign and contribute to the data analysis.
- Forschungsfeld
- Teilchen und Felder (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
- Betreuer(innen)
- Karina Bernert
|
|
|
Chimären-Zustände in asymmetrischen 2-Populationsnetzwerken |
Krischer |
- Arbeitsgruppe
- Chemische Physik fern des Gleichgewichts
- Beschreibung
- In this theoretical project from the field of Nonlinear Dynamics, the collective dynamics of coupled oscillators shall be explored. More precisely, the dynamics of two interacting sets - or populations - of oscillators shall be studied. It has been shown that symmetric two-population networks, where each population consists of the same number of oscillators, might exhibit a symmetry-breaking to a so-called chimera state, characterized by the coexistence of coherence and incoherence. In this project, the dynamics of asymmetric networks with different population sizes shall be explored, with particular emphasis on the existence of chimeras. The projects includes both analytical and numerical investigations.
- Forschungsfeld
- Betreuer(innen)
- Seungjae Lee
|
|
|
Computersimulation der Bindung von Peptiden an RNA |
Zacharias |
- Arbeitsgruppe
- Molekulardynamik
- Beschreibung
- RNA molecules are involved in many processes in cells. Typically, these processes involve the interaction with proteins and peptides. There are specific short peptide segments that often mediate the interaction between proteins and RNA. In the BSc thesis project the binding of short tripeptides with a central Arginine residue (often part of RNA binding peptides) and RNA will be studied using Molecular Dynamics simulations. Aim is to identify and characterize the preferred binding sites on the RNA molecules. It is hoped that it will allow the prediction of how and where larger proteins (that contain such short RNA binding motifs) bind to RNA molecules.
- Forschungsfeld
- Biologische Physik (Theorie)
|
|
|
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)
|
|
|
Construction and qualification of the Precision Optical Calibration Modules (POCAMs) for the IceCube Upgrade project. |
Resconi |
|
|
|
|
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 (bachelor) students on Wednesday, February 1, 14:00-16:00. For more information please check at https://www.moodle.tum.de/course/view.php?id=85828 and register. Also, please send an email to schoenert@ph.tum.de and add your name to here: https://docs.google.com/document/d/14U-KQA-z-QCrTRaDm6SSNjrUNbmsCv9qe1k6wbGNSus/edit?usp=sharing . Also students interested in a master thesis project are welcome to join the meeting. - Forschungsfeld
- Astrophysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~30%)
- Kernphysik (experimentell) (~20%)
- Festkörperphysik (experimentell) (~20%)
|
|
|
Data analysis of X-ray/neutron scattering images using Jupyter Notebook |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
When grazing incidence X-ray/neutron scattering experiments on thin films are performed, we obtain 2d scattering patterns. The data analysis typically involves reduction from 2d to 1d lines and then model-fitting using certain assumptions for the morphology and the interference between the nanosized domains in the films. However, the 2d images can also be simulated by existing softwares (e.g. BornAgain) if precise assumptions for the morphology are made. The 2d model-fitting can be a very successful understanding of the real morphology. Given the popularity of Python as data analysis language in natural sciences, a robust analysis requires adaptation of existing modelling algorithms to Jupyter notebooks. In this project you will export existing modelling scripts from BornAgain software to Jupyter notebook. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Development of Microfluidic devices for Angiogenesis Assays |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Beschreibung
- Angiogenesis bezeichnet die Bildung von Blutgefässen, die eine zentrale Rolle bei der Entwicklung von höheren Lebewesen spielt, aber auch bei Tumorwachstum. Hier soll ein Assay entwickelt werden, welches es Erlaubt die Bildung der Blutgefässe zu beobachten Zile ist es die Interaktion der Blutgefässsen mit Tumor-Organoiden beobachtbar zu machen.
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
Development of new approach to study particle correlations using femtoscopy |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- One of the most precise and most powerful approaches to probe the strong interaction between different particle pairs is the femtoscopy method [1] which is based on measuring the correlation in the momentum space between hadrons produced at particle colliders such as the LHC. The correlation function is obtained by using the same and mixed event particle pair distributions as functions of their relative momenta. The former carries the information about the interaction while the latter provides information on the available phase-space of the produced pair.
Two particles produced in one collision makes the same event pair while the mixed event pairs are constructed by taking two particles from two di erent collisions. The technique of event mixing is a very well working approximation, however, more sophisticated solutions are of increasing interest as the femtoscopic method is used in more and more complicated studies and is being extended to probe the multi-hadron interactions.
In this work, a new approach to account for the particle phase space will be elaborated by using marginalized probability distribution functions. Toy Monte Carlo simulations will be used to test the mathematical basis of the method which will be then applied on the proton-proton collision data collected by the ALICE detector to study its feasibility in real experimental conditions.
[1] Hadron-hadron interactions measured by ALICE at the LHC, L. Fabbietti, V. Mantovani
Sarti, O. V azquez Doce, arXiv: 2012.09806 (2020)
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Laura Serksnyte
|
|
|
Dynamik im stark korrelierten Hubbard Modell |
Knap |
|
|
|
|
Dynamische Tight-Binding Methode für Halbleiter |
Egger |
- Arbeitsgruppe
- Theorie funktionaler Energiematerialien
- Beschreibung
-
| In this project, the student will investigate the effect of disorder, defects and impurities on the electronic bandstructure of semiconductors using computational methods within density functional theory and band unfolding. |
- Forschungsfeld
- Festkörperphysik (Theorie)
|
|
|
Effect of microwave irradiation on the morphology and performance of PEDOT:PSS electrodes |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- It is generally acknowledged that treating PEDOT:PSS with certain additives, such as ethylene glycol (EG), dimethyl sulfoxide (DMSO) and sorbitol, has been shown to increase the conductivity by several orders of magnitude. Moreover, drying method seems to play a big role in the morphology and performance of this material. Using a slow drying method via the commonly used hot plate, additive can induce an obvious separation between free PSS and reorganized PEDOT:PSS complexes in the highly conductive PEDOT:PSS films. Upon complete drying, PSS formed a transparent rim film around the conducting PEDOT film, resulting in the inhomogeneous film. Here, microwave irradiation is expected to rapidly and evenly heat the PEDOT:PSS film. The solidifying time can be easily controlled by adjusting microwave power and irradiation time. We anticipate that the controllable separation between PSS and PEDOT will pave the path to designing strategies to process high-performance PEDOT:PSS electrodes.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Effect of moisture on the morphology and electrical performance of mesoporous ZnO film |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
Moisture can strongly influence the conductivity of ZnO semiconductors via the physisorption and chemisorption of water molecules on the ZnO surface. Mesoporous ZnO structures can facilitate the absorption process by providing a large surface area and active sites, and thus can be used as a sensor to monitor humidity changes. However, little effort has been devoted yet to gain an in-depth understanding of the effect of water on morphology and electrical property. In this work, different mesoporous ZnO thin films will be explored by exploiting different diblock copolymers as structure-directing agents. The film morphologies will be checked by a combination of real-space scanning electron microscopy and reciprocal-space grazing-incidence small-angle X-ray scattering techniques. Consequently, information about both the surface and inner nanostructures will be provided. To evaluate the sensing performance, in situ electrochemical impedance spectroscopy will be used to monitor the conductivity changes. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Effiziente Produktion von Positronenemitter mittels Protonenstrahl (Thema ist bereits vergeben) |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
Small, weak positron sources are in enormous demand worldwide for positron experiments on a laboratory scale. In order to enable the simple production of such compact positron emitters, a new concept is being pursued in this pilot project, in which complex processing such as wet-chemical processes is completely eliminated. In this work, the depth-dependent activity (Na-22) generated by proton irradiation in aluminum is to be determined and compared with the calculated depth distribution. The irradiation will be performed in cooperation with the HZB Berlin. The project is carried out within the TUM research group Physics with Positrons. - Forschungsfeld
- interdisziplinäre Themen (experimentell) (~40%)
- Festkörperphysik (experimentell) (~20%)
- Materialphysik (experimentell) (~20%)
- Kernphysik (experimentell) (~20%)
|
|
|
Entwicklung eines neuen Silizium Detektor mit der CMOS Technologie |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- In dieser Arbeit wollen wir einen Prototyp für einen ultradünnen Siliziumdetektor der nächsten Generation für die Hochenergie-Teilchenphysik entwickeln, der die CMOS-Technologie nutzt. Ziel ist es, einen echten 3-D-Tracker zu bauen, der aus ultradünnen und biegbaren Detektoren besteht, und ein Experiment an einem kleinen Beschleuniger durchzuführen, um die Auflösung des Aufbaus mit Hilfe von elastischen pp-Kollisionen zu bestimmen. Die Arbeit umfasst die Arbeit im Labor, den Entwurf der mechanischen Struktur der Detektoren, die Prüfung der Sensoren und die Teilnahme an Tests.
- Forschungsfeld
- Teilchen und Felder (experimentell)
|
|
|
Environmentally friendly perovskite solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
The power conversion efficiency of lead-based perovskite solar cells reached champion values of 25.8 %. However, the environmental unfriendliness and instability in ambient conditions of lead-based solar cells is detrimental to its commercial application. Lead-free double perovskite is regarded as one of the ideal candidates to replace the toxic lead-based perovskite in next generation solar cells and make such solar cells environmentally friendly. Today its optical properties are not yet fully understood. Herein, we will fabricate lead-free double perovskite thin films by spin-coating or printing method, and investigate its optical properties by photoluminescence spectroscopy and UV-Vis spectroscopy to pave the way for application in next generation solar cells. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Ferromagnetische Resonanzmessungen bis 65 GHz |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- In this project we would like to extend the frequency range for ferromagnetic resonance experiments in an existing set-up to 65 GHz. Test measurements will be performed on selected thin film ferromagnets.
- Forschungsfeld
- Festkörperphysik (experimentell)
|
|
|
Fokussierung eines Positronenstrahls zur tiefenaufgelösten Defektspektroskopie |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
Unser Doppler-Verbreiterungsspektrometer ist ein hervorragendes Werkzeug zur Bestimmung der Defektkonzentration in Festkörpern. Hierzu verwenden wir einen monoenergetischen Positronenstrahl, der durch das Anlegen einer (Hoch-)Spannung auf die Probe beschleunigt wird. Die Stahlführung erfolgt durch eine Kombination aus magnetischen und elektrischen Feldern. Ziel der Bachelorarbeit ist es, die Strahlführungsparameter für einen optimalen Strahlfokus speziell im Energiebereich von wenigen eV zu optimieren und erste Messungen zur Positroniumsbildung an Oberflächen durchzuführen.
Das Projekt wird in der TUM Forschungsgruppe Physik mit Positronen durchgeführt. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Teilchen und Felder (experimentell) (~30%)
- interdisziplinäre Themen (experimentell) (~20%)
|
|
|
Fragmentierung in massereichen Molekuelwolken-Klumpen |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- What determines a star's final mass is a fundamental, still unsolved question in star formation research. Thermal pressure in a cloud fragment counteracts gravity, hence the temperature of the dense, star forming gas could be expected to influence the mass needed to make the cloud fragment (core) unstable to collapse and form a star.
The aim of this project will be to investigate the small scale structure within a number of dense clumps with previously measured gas temperatures. We will use archival sub-millimetre wavelength radio continuum data (tracing emission from cold dust mixed with the gas) obtained with the ALMA interferometric radio telescope. Applying different algorithms to characterize the clumps substructure it will be investigated whether there are systematic differences in the small scale structure as the clumps temperature varies, such as differences in the core mass distribution and/or
separation, that could hint at a dependence of the cores masses (and resulting stellar mass) on the dense gas temperature.
The project includes elements from computational and observational
sub-mm radio astrophysics and will provide basic knowledge in the field of star formation. Some background in astrophysics is advantageous, but affinity and basic knowledge in Python programming is a must.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
|
|
|
Gold nanoparticles for optoelectronic devices |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Gold nanoparticles (Au NPs) show peculiar optical and electrical properties compared with macroscopic metal owing to their unique capability of concentrating, routing, and manipulating light at the nanoscale. Recently many advantages were made in optoelectronic devices applications with broadening band and energy transfer. In this project, your work will focus on investigating doping Au NPs in optoelectronic film, since the size, density, and morphology of the Au NPs will influence the crystallinity of the photoactive film and charge transport of the device. We will use UV-vis, SEM, and x-ray scattering to investigate the optical properties and morphology of the hybrid nanostructures. Specific focus will be on the correlation between optical properties and the morphology of the Au NPs as well as the self-assembly of monolayer Au NPs array for optoelectronic devices.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Gravitationswellen (Thema ist bereits vergeben) |
Weiler |
- Arbeitsgruppe
- Theoretische Teilchenphysik an Collidern
- Beschreibung
- The thesis explores the theoretical background and the recent discovery of gravitational waves by the LIGO collaboration.
The goal is to derive the gravitational wave equation using a linearized Einstein-Hilbert action, establish the degrees of freedom and the helicity of gravitational waves and discuss the TT frame versus the proper detector frame. Finally, we will use these methods to interpret a black hole merger event as measured by the LIGO collaboration and extract the masses of the black holes.
- Forschungsfeld
- Teilchen und Felder (Theorie) (~80%)
- Astrophysik (Theorie) (~20%)
|
|
|
Imaging single molecule mitochondrial DNA replication dynamics in live budding yeast cells |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Beschreibung
- Mitochondrial DNA (mtDNA) is essential to mitochondria functions since it encodes for subunits of the respiratory chain. Defects in mtDNA maintenance and altered mtDNA copy number are linked to metabolic and neurodegenerative diseases, as well as many types of cancer. mtDNA is organised in nucleoproteins called nucleoids, which are distributed throughout the mitochondrial network. Despite the fundamental importance for cell function, the mechanisms that control replication of mtDNA and formation of new nucleoids are poorly understood.
In this project at the Helmholtz Institute in the group of Dr. Kurt Schmoller, we will employ cutting-edge live-cell imaging techniques in combination with a minimally invasive mtDNA labelling approach to follow individual mtDNA replication events in the budding yeast S. cerevisiae. To automatically extract reliable and quantitative information from time-lapse data, we will develop novel machine learning image analysis approaches.
The project is highly interdisciplinary, spanning molecular biology, cell biology and biophysics, and offers opportunities for both experimental and computational work. This includes genetic manipulation of budding yeast cells along with performing advanced experiments using microfluidics-based live-cell confocal microscopy. In addition, we will apply and develop a mixture of computer vision techniques to analyse the images produced.
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
Implementation eines automatischen Triangulations-Algorithmus (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are flashes of gamma-rays resulting from either the death of massive stars (leading to long-duration GRBs) or the merger of two neutron stars (short-duration GRBs). Since the discovery of gravitational waves in conjunction with a short GRB in August 2017, the quest of accurately localizing short GRBs is of utmost importance. Present detectors with good localization capability detect predominantly long-duration GRBs, while detectors sensitive to short GRBs have bad localization accuracy.
The thesis shall take our code for triangulation of GRB lightcurves from two satellites, and implement it in our existing GRB reduction pipeline for the Fermi-GBM satellite by adding the INTEGRAL/ACS data. This shall allow to rapidly (within minutes)
provide accurate localization annuli, providing a rapid cross-check of the Fermi-only localization.
Technically, this thesis involves learning of (i) data analysis of non-imaging gamma-ray detectors, (ii) understanding and correcting detector effects, (iii) understanding low-count and Bayesian statistics, and (iv) learn about the forward-folding approach for light curve cross-correlation which is independent of the temporal binning of the data.
Some background in astrophysics is advantegeous. Python knowledge is required, and good programming skills and interest in Bayesian statistics are helpful. Joy in data analysis is required.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
|
|
|
Improving the Stability Window of Aqueous Electrolytes as a Way Towards High-Energy Aqueous Potassium-Ion Batteries |
Bandarenka |
|
|
|
|
Konsistente Initialisierung von supra-thermischen Teilchen zur Simulation der Wechselwirkung mit Instabilitäten in Fusionsplasmen mit magnetischem Einschluss |
Günter |
- Arbeitsgruppe
- Max-Planck-Institut für Plasmaphysik (IPP)
- Beschreibung
- Certain processes in magnetic confinement fusion devices require a kinetic treatment of the plasma, while others can be described in a simpler fluid picture. Hybrid fluid-kinetic models are often used, where particle species are described differently. For instance, the interaction of energetic particles (EPs), such as the ones born directly by the fusion processes, with the plasma background is often treated in such a hybrid way. For very non-linear processes, the full distribution function of the kinetic particles needs to be modeled with “markers”, called a full-f model. Since particles are not exactly following the magnetic flux surfaces, a “naive” initialization of markers can lead to a strong unrealistic relaxation of the distribution function when such a full-f description is used [1] causing an artificially reduced growth rate for EP driven instabilities. It is therefore important to construct the marker distribution in the constant of motion space (e.g. like described in [2,3]). In this project, the energetic particle model of the non-linear MHD code JOREK [4,1] will be enhanced to avoid such spurious relaxation effects.
First, an existing case, in which particles are not loaded based on their conserved quantities, will be studied to investigate the relaxation of the initial distribution function. Also linear properties of the unstable mode driven by this relaxed EP distribution will be studied.
Next, a method previously developed for the initialization of thermal particles will be adapted for the initialization of EPs based on conserved quantities. The method will be extended where needed and then be applied to the previously tested case to demonstrate that the particle distribution does not relax any more. The linear growth rate of EP driven instabilities will be benchmarked against literature and compared to the previous results with relaxation.
[1] Bogaarts T.J., Hoelzl M., Huijsmans G.T.A., Wang X., JOREK Team. Physics of Plasmas 29, 122501 (2022).
[2] Angelino P, et al, Physics of Plasmas 13, 052304 (2006)
[3] Lu Z., et al 2022 https://arxiv.org/abs/2210.04354
[4] Hoelzl M., Huijsmans G.T.A., Pamela S.J.P., Becoulet M., Nardon E., Artol
- Forschungsfeld
- Plasmaphysik (Theorie)
|
|
|
Kontrolle der Austauschwechselwirkung durch elektrische Felder |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
Es ist bekannt, dass die Austauschwechselwirkung erstmals von Heisenberg vor etwa 100 Jahren vorgeschlagen wurde. Ist ein Material erst einmal präpariert, so wird im Allgemeinen davon ausgegangen, dass es nicht möglich ist, die Größe der Austauschwechselwirkung zu ändern. Dieses Projekt zielt darauf ab, ein externes elektrisches Feld zur Kontrolle der Austauschwechselwirkung in ferromagnetischen Metallen zu nutzen. Zur Untersuchung der Steuerung durch ein elektrisches Feld verwenden wir ultradünnes Fe, das durch Molekularstrahlepitaxie auf einem Pt(111)-Substrat aufgewachsen ist. Ein Feldeffekttransistor wird mit Hilfe von Elektronenstrahllithographie hergestellt, und Magneto-Transport, magnetisch-optische und ferromagnetische Resonanztechniken werden zur Charakterisierung verwendet.
--------------------------------------------------------------------------------------------------------------------------------------
It is known that the exchange interaction was first proposed by Heisenberg about 100 years ago. Once a material is prepared, it is generally assumed that it is not possible to change the magnitude of the exchange interaction. This project aims to use an external electric-field to control the exchange interaction in ferromagnetic metals. Here, to study the electric-field control, we use ultrathin Fe grown on Pt(111) substrate by molecular-beam epitaxy. A field-effect transistor device will be fabricated by electron-beam lithography, and magneto-transport, magnetic-optical and ferromagnetic resonance techniques will be used in this study. - Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Lin Chen
|
|
|
Kontrolle der Spin-Orbit-Torques in ultradünnen Fe/Pt Bi-Lagen durch elektrische Felder |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- Spin-Orbit-Torques (SOTs) which can be used to manipulate the magnetization of thin ferromagnetic layers can be generated at interfaces to heavy metals such as Platinum. In this thesis we will attempt to modify the strength and direction of SOTs in thin bi-layers of Pt and Fe.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Lin Chen
|
|
|
Landauniveaus, Eich- und Verschiebungsinvarianz |
Garbrecht |
- Arbeitsgruppe
- Theoretische Physik des frühen Universums
- Beschreibung
The system consisting of a charged point particle in a homogeneous magnetic field is translation invariant in the plane perpendicular to the field. Consequently, the Lagrangian and Hamiltonian are invariant up to a total time derivative. Yet, there is no gauge in which the quantized Hamiltonian manifests this symmetry. Translations are then tantamount to gauge transformations. We aim to pin where the the loss of manifest tranlation invariance occurs and to see whether it can be circumvented. As one line of the analysis we shall construct the path integral from the quantized theory, where we expect translation invariance to be manifest once again. Further, we will consider general models where the Hamiltonian requires some form of gauge fixing. - Forschungsfeld
- Teilchen und Felder (Theorie)
|
|
|
Lebensdauermessung von Protonemittern am R3B Experiment |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- Protonenradioaktivität ist ein, seit einigen Dekaden experimentell verifiziertes Phänomen, das unter anderem auch an der TU-München entdeckt wurde. Trotzdem sind die Lebensdauern für die meisten Protonemitter noch nicht, oder nur sehr ungenau vermessen. Wir wollen im Rahmen eines BMBF geförderten Projektes eine neuartige Methode für diese Messungen etablieren und damit ein umfangreiches Messprogramm zusammen mit der R3B Kollaboration bei FAIR in Darmstadt beginnen.
Das R3B – Experiment (Reactions with Relativistic Radioactive Beams) spielt eine herausragende Rolle bei der Untersuchung exotischer Kerne mit extremem Proton zu Neutron Verhältnis. Ein zentraler Detektor in diesem Projekt ist das, aus mehreren tausend Einzelkristallen bestehende, CALIFA Kalorimeter, das einen hochselektiven Trigger für die quasifreie Streuung liefert. Wir wollen damit und einem gerade im Aufbau befindlichen, hochauflösenden Silizium Tracking-Array durch Vertex-Rekonstruktion die Lebensdauer kurzlebiger Kerne vermessen.
Im Rahmen einer Masterarbeit sollen dafür zum einen erste Simulationsrechnungen gemacht werden, die den Parameterbereich der Methode eingrenzen, zum andern soll das Detektorsystem in einem ersten Experiment bereits im kommenden Frühjahr untersucht und charakterisiert werden.
ADVISOR: Prof. L. Fabbietti / Dr. R. Gernhäuser
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Roman Gernhäuser
|
|
|
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 bachelor students on Wednesday, February 1, 14:00-16:00. For more information please check (https://www.moodle.tum.de/course/view.php?id=85828). Until then, please send an email to schoenert@ph.tum.de and add your name at this document https://docs.google.com/document/d/14U-KQA-z-QCrTRaDm6SSNjrUNbmsCv9qe1k6wbGNSus/edit?usp=sharing . Also students interested in a master thesis are welcome to join. - Forschungsfeld
- Atomphysik (experimentell) (~30%)
- Teilchen und Felder (experimentell) (~30%)
- Kernphysik (experimentell) (~20%)
- Festkörperphysik (experimentell) (~20%)
|
|
|
Lokalisierung von Gamma Ray Bursts mittels Triangulation (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are flashes of gamma-rays resulting from either the death of massive stars (leading to long-duration GRBs) or the merger of two neutron stars (short-duration GRBs). Since the discovery of gravitational waves in conjunction with a short GRB in August 2017, the quest of accurately localizing short GRBs is of utmost importance. Present detectors with good localization capability detect predominantly long-duration GRBs, while detectors sensitive to short GRBs have bad localization accuracy.
We have developed a new concept for GRB light curve cross-correlation using Bayesian model forward-folding, which should provide more accurate localisations for GRBs than previous triangulation methods. This has been demonstrated with simulations. The thesis shall take our code and apply it to real data, to verify is performance.
Technically, this thesis involves learning of (i) data analysis of non-imaging gamma-ray detectors, (ii) understanding and correcting detector effects, (iii) understanding low-count and Bayesian statistics, and (iv) learn about the forward-folding approach for light curve cross-correlation which is independent of the temporal binning of the data.
Some background in astrophysics is advantageous. Python knowledge is required, and good programming skills and interest in Bayesian statistics are helpful. Joy in data analysis is required.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
|
|
|
Lokalisierung von Transienten Gamma-Quellen |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
The 2017 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. Similarly, the production of gamma-ray flares coincident with fast radio bursts is a mystery. 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 be devoted to improve this pipeline, and establish a Python program for checking for potential counterparts of these newly identified transients in existing data of the Swift/BAT survey, with the goal of an identification and good localization.
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)
|
|
|
Low Energy Electron Diffraction an supramolekularen Netzwerken auf Graphit |
Lackinger |
- Arbeitsgruppe
- Lehrstuhl für Wissenschaftskommunikation (Prof. Heckl)
- Beschreibung
- Die Epitaxie kristalliner molekularer Schichten zum darunterliegenden Substrat lässt sich hervorragend mittels oberflächensensitiver Elektronenbeugung – Low Energy Electron Diffraction (LEED) - charakterisieren. Gegenstand der aktuellen Arbeit ist die Untersuchung von über Wasserstoffbrückenbindungen stabilisierten Netzwerken der Trimesinsäure (TMA) auf natürlichen Graphit Einkristallen. Die TMA Monolagen werden durch thermische Sublimation im Ultra-Hoch-Vakuum präpariert. Vorangegangene Studien zeigten, dass die TMA-Überstruktur inkommensurabel zum Graphit ist. Interessanterweise ist dabei der Winkel zwischen TMA- und Graphit-Gitter nicht fest, sondern weist eine gewisse Schwankungsbreite um eine Vorzugsorientierung auf. In der aktuellen Arbeit soll nun systematisch untersucht werden, ob durch Variation der beiden maßgeblichen Präparationsparameter, d.h. Temperatur des Graphit-Substrats bei der Abscheidung und TMA Abscheidungsrate, eine gezielte Beeinflussung der Epitaxie in diesem System möglich ist.
Diese experimentelle Arbeit ist in den Nanolaboren am Deutschen Museum angesiedelt.
- Forschungsfeld
- Oberflächenphysik (experimentell)
|
|
|
Mapping network theory to network function |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Networks exist as our social network, the world wide web, traffic routes but also as flow networks making up the vasculature of animals, plants, fungi and slime moulds. While a lot of measures have been developed to describe networks in general it is not clear how these measures are predicting network function via network architecture. You will quantify physical networks of the slime mould and numerically generated model networks with network theoretic measures. Mapping to slime mould behaviour and model network flow and transport function will allow you to identify predictive network theoretic measures. You will learn network theory, Matlab. Prerequisites: statistical physics.
Task 1 Collect network theoretic measures from the literature and Matlab packages
Task 2 Apply network theoretic measures on slime mould and model data and map their property onto the network architecture
Task 3 Correlate link by link network theoretic measure and flow/transport in the link under inspection to identify measures of predictive power.
- Forschungsfeld
- Biologische Physik (Theorie) (~50%)
- Biologische Physik (experimentell) (~10%)
- interdisziplinäre Themen (experimentell) (~10%)
- interdisziplinäre Themen (Theorie) (~30%)
|
|
|
Mechanosynthetic lithiation of 2H graphite |
Petry |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- The high demand on portable electronic devices paves the way to energy storage systems with higher energy/power densities at lower costs like lithium-ion batteries. One of the most used negative electrode material in state-of-the-art lithium-ion batteries is high performance graphite. In order to understand de-/lithiation and degradation mechanisms of graphite, a mechanosynthetical lithiation (ball milling) is proposed in this project to prepare differently lithiated phases corresponding to electrochemical stages in real lithium-ion batteries. Parameters, like frequency, temperature and time have to be optimized in order to produce lithiated phases of desired content and quality. X-ray diffraction will be used for the validation of the-synthesized materials.
Common supervision is foreseen with Dr. Anatoliy Senyshyn, diffraction group leader at MLZ.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
- Betreuer(innen)
- Anatoliy Senyshyn
|
|
|
Modelling single photon sources for optical quantum circuits (Thema ist bereits vergeben) |
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%)
|
|
|
Molekulare Simulation der Faltung von Amyloidstrukturen |
Zacharias |
- Arbeitsgruppe
- Molekulardynamik
- Beschreibung
- Natural proteins typically form stable globular structures. However, approximately 30% of natural proteins do not adopt a single stable structure but adopt a so called disordered state. Disordered proteins but also mutated globular proteins can aggregate to form regular amyloid structures. Such structures are involved in many diseases. In the BSc-project a computational methodologyto predict the amyloid structure of protein sequences will be developed and tested. The method is based on including information extracted from known amyloid structures to guide molecular dynamyics simulations.
- Forschungsfeld
- Biologische Physik (Theorie)
|
|
|
Nanogenerator based wearable electronics for multi-dimensional sensing with machine learning assistance |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
Triboelectric nanogenerator originating from Maxwell’s displacement current is a new kind of technology, which can convert mechanical signals into electrical signals for further processes. Recently, many triboelectric nanogenerators have been fabricated as vertical pressure sensors. In this project, your work will focus on the fabrication of new triboelectric nanogenerator based wearable sensor systems. Moreover, machine learning technology will be introduced to systems for high-precision recognition. Both electrical measurements and signal collection by microcontrollers will be learned in this project. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
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, the pulser system will be put in 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
|
|
|
Optical readout of spin ensembles |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Electron spin resonance provides means to very sensitive magnetic field sensors. At present charged nitrogen vacancies in diamond provide unique properties such as optical readout of the electron spin state and spin coherence above room temperature. This allows to use this system for magnetic field sensing applications. You will work on implementing an experimental platform for optical readout and microwave manipulation of electron spins in nitrogen vacancy centers in your thesis.
For the setup you will use optical detection schemes and laser illumination. In addition, you employ microwave signals to manipulate the spin state in the nitrogen vacancy center. You will then use calibration measurements to quantify the performance of the new setup.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Patricia Oehrl
- Matthias Althammer
- Hans-Gregor Hübl
|
|
|
Optimierung des elektrochemischen Herstellungsprozesses einer nanostrukturierten Kupferelektrode mit Rasterelektronenmikroskopie |
Krischer |
- Arbeitsgruppe
- Chemische Physik fern des Gleichgewichts
- Beschreibung
- Die CO2-Reduktion ist die elektrochemische Aufwertung von CO2-Gas zu Kohlenwasserstoffen und organischen Molekülen. Dabei ist die Vorstrukturierung des zu verwendenden Katalysators, in diesem Fall Kupferoxid, essenziell für die Effizienz und die Produktzusammensetzung der Reduktion. In dieser Arbeit soll ein existierender elektrochemischer Herstellungsprozess für Kupferoxidelektroden optimiert werden. Diese Untersuchung wird primär mit Rasterelektronenmikroskopie durchgeführt, aber auch elektrochemische Methoden und gaschromatographische Produktanalyse kommen zur Anwendung.
- Forschungsfeld
- Chemische Physik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
- Betreuer(innen)
- Hagen Übele
|
|
|
Optimierung von auf maschinellem Lernen basierter Wachstumsvorhersage für Zellkulturexperimente |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
Organoid Development |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Beschreibung
- Organoide sind Mini-Organe, die aus einzelnen Zellen im Labor wachsen. Im Rahmen der Arbeit sollen Pankreas Krebs Organoide untersucht werden, und die Dynamik des Wachstum und der Differenzierung untersucht werden. Zum Einsatz kommen hochauflösende Mikroskopiemethoden und digitale Bildverarbeitung.
- Forschungsfeld
- Biologische Physik (experimentell)
- Betreuer(innen)
- Andreas Bausch
|
|
|
Our gut moves, and it matters |
Alim |
- Arbeitsgruppe
- Theorie biologischer Netzwerke
- Beschreibung
- Our gut is the center of food absorption. However, the gut is not just a still tube: its walls contract to produce fluid flows that propel the food onward and mix it. Indeed, our gut varies the contraction patterns during the day; the fluid characteristics like viscosity and rheological properties may also vary during the day due to the food content. However, it is not entirely clear yet how these different elements vary the food transport. Therefore, you will investigate how different contraction patterns and different fluid characteristics (Newtonian and non-newtonian fluids) change the flow. You will additionally study how this impacts the transport of nutrients. You will learn about fluid flows and transport, Comsol. Prerequisites: differential equations
Task 1 Implement in Comsol contracting walls with specific contraction patterns with Comsol package “Deformed Geometry (dg)”
Task 2 Calculate the corresponding fluid flow for different viscosities and fluid types
Task 3 Calculate solute distribution with the “Transport of Diluted Species in Porous Media (tds)” package and compare it to previous work from the group and literature
- Forschungsfeld
- Biologische Physik (Theorie) (~70%)
- Physik der weichen Materie (Theorie) (~30%)
|
|
|
Performance and Stability of Organic Anode Materials for Aqueous Potassium-Ion Batteries |
Bandarenka |
|
|
|
|
Performance and Stability of Prussian Blue Analogue Based Cathodes for Aqueous Potassium-Ion Batteries |
Bandarenka |
|
|
|
|
Piezoelectric response of AlN thin films |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Micro electro-mechanical systems are an important building block for miniaturized sensor and actuator applications. This requires thin films with piezoelectric properties. Among them, AlN provides unique advantages for integration into Si-based electronics and optoelectronics. Doping with rare earth elements leads to a distortion of the hexagonal lattice and can even enhance the piezoelectric response. The goal of this thesis is the optimization of AlN sputter deposited thin films in regards to their piezoelectric properties. You will investigate the role of doping on the piezoelectric properties.
In your thesis, you will use state-of-the-art thin film sputter deposition to optimize the growth by tuning the deposition conditions. You then will employ structural analysis using X-ray diffraction to investigate the epitaxial properties of the deposited thin films. In addition, you will characterize the piezoelectric properties and ferroelectric domain structure by piezo-force microscopy techniques.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Matthias Althammer
|
|
|
Polymer electrolyte for high voltage lithium metal batteries |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
- Lithium metal batteries has been widely applied in our daily life since recent years. It is essential to develop new materials to meet the increasing requirements such as stability, safety and manufacturing costs. In this project, we aim to fabricate polymer electrolyte materials which can realize high voltage fast charge/discharge for next generation electric vehicles (EVs). Varies types of coin cell is built for the battery performance test like charge/discharge simulation and electrochemical property evaluation.
- Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
P-ONE: Entwicklung des Optischen Modules |
Resconi |
|
|
|
|
Printed 2D perovskite solar cells |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
Printed perovskite solar cells will make a future contribution to energy conversion, but so far, device stability hinders their commercial success. Two-dimensional (2D) perovskite solar cells have superior stability compared to their 3D counterparts, however, their power conversion efficiency is still far behind 3D perovskite solar cells. Such behavior is correlated with preferred 2D perovskite growing along the in-plane direction with respect to the substrate, therefore the insulating bulky organic cation impedes the out-of-plane charge transfer and causes the insufficient charge transport. In this perspective, we aim to understand perovskite growth mechanism and control perovskite growth at large scale during printing. This project includes the literature review, state-of-the-art fabrication method, and advanced spectroscopy technique. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
Quantum acoustics with mechanical nanostrings |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
The field of quantum acoustics aims to investigate quantum mechanical effects in acoustic resonator structures. Combined with e.g. optical and / or superconducting circuits, this offers the possibility to create quantum hybrid systems, which are discussed in the context of storing and converting quantum states. In this project, we shall investigate one of the building blocks, i.e. a mechanical nanostring resonator with a superconducting thin film. With your help, we aim to develop and optimize nanostring resonators operating in the GHz frequency range with high quality factors and test these devices at moderately low (3-10K) temperatures.
Your bachelor thesis will bring you in touch with state-of-the-art nanofabrication technology and introduce you to microwave spectroscopy tools like vector network analyzers, as well as optical measurements in a cryogenic environment. Careful data analysis of the laser interferometry data of these resonators combined with modeling will put you in the position, to make a meaningful contribution to the creation of quantum hybrid systems. - Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Matthias Althammer
- Hans-Gregor Hübl
|
|
|
Quench protection for a superconducting magnet |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- The generation of magnetic fields with electrical currents is deployed in multiple systems, such as generators, motors, MRI systems, up to particle accelerators and fusion reactors. In laboratory, we use superconducting magnets, which allow to generate magnetic fields at cryogenic conditions to manipulate the electronic spin transitions of paramagnetic ions. However, superconducting magnets may undergo a spontaneous transition into the normal state - a so-called quenching process. Such event would result in the generation of a large thermal energy, which is increasing with the size of the magnet. Such amount of thermal energy is enormous for a magnet placed in a cryostat below 4K. Solutions allowing to protect the magnet in case of a quench are called quench protection circuits.
In this project, you are offered to develop a quench protection circuit for an existing superconducting magnet. During the project you will learn about cryogenics, the generation of magnetic fields, superconducting magnets and design of electrical circuits.
We are looking for a highly motivated bachelor student joining this project. During this project you will work in an international team at Walther-Meißner-Institute.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Jianpeng Chen
- Nadezhda Kukharchyk
|
|
|
Raman Spektroskopie mittels Molekulardynamik |
Egger |
- Arbeitsgruppe
- Theorie funktionaler Energiematerialien
- Beschreibung
- This project is about calculations of Raman spectra for molecules and crystals using autocorrelation functions, molecular dynamics (MD) and density functional theory.
- Forschungsfeld
- Festkörperphysik (Theorie)
|
|
|
Raman Spektroskopie mittels Phononen |
Egger |
- Arbeitsgruppe
- Theorie funktionaler Energiematerialien
- Beschreibung
- This project is about calculations of Raman spectra for molecules and crystals using phonon- and density functional theory.
- Forschungsfeld
- Festkörperphysik (Theorie)
|
|
|
Rekonstituion von Zelladhäsionskomplexen |
Bausch |
- Arbeitsgruppe
- Zellbiophysik
- Beschreibung
- Adhäsion von Zellen zur Extrazellulären Matrix sind Voraussetzung für die Entwicklung von komplexen Lebewesen. Dabei ist die Adhäsion Voraussetzung für die beobachtete Mechanosensitivität von Zellen. In dieser Arbeit sollen Minimale Adhäsionskomplexe in vitro nachgebaut werden. Durch die Kombination eines Mikrofluidik-Setups mit Festkörpergestützten Membranen soll die Bildung der Adäsionskomplexe quantifiziert werden.
- Forschungsfeld
- Biologische Physik (experimentell)
|
|
|
Schnelle Transient-Identifikation fuer Satelliten-Anwendung (Thema ist bereits vergeben) |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are flashes of gamma-ray resulting from the death of massive stars or the merger of neutron stars. They are followed by an `afterglow' signal that can be detected from radio to X-rays, produced by a shock wave moving into the gas surrounding the burster at approximately the speed of light. This afterglow emission can be much better localized than the gamma-rays. Due to downlink constraints from a satellite, this localization has to be done onboard, in order to allow communication of new transients within minutes, and consequently follow-up by other facilities.
This thesis shall take an existing data reduction and catalog matching pipeline for optical data, speed it up by >10x, and change the catalog matching from Internet access to internal memory access by minimizing the memory requirements by >10x. Technically, this involves (i) understanding multi-filter optical data, (ii) learn source detection routines, (iii) identify a fast and reliable astrometry routine, (iv) understand fast catalog matching, and (v) learn memory-saving matrix operations.
The project includes elements from computational and observational high-energy astrophysics, and will allow for obtaining extensive knowledge on gamma-ray bursts and related phenomena. Some background in astrophysics is advantegeous, but joy and experience in Python programming is absolutely required.
Contact: Jochen Greiner, jcg@mpe.mpg.de, MPE Room 1.3.13, Tel. 30000-3847
- Forschungsfeld
- Astrophysik (experimentell)
|
|
|
Simulation von Elastic Recoil Detection Analysis (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)
|
|
|
Specific Ion Effects on Co-nonsolvency Induced Phase Transition Behavior of Thermoresponsive Homopolymer Thin Films |
Müller-Buschbaum |
- Arbeitsgruppe
- Funktionelle Materialien
- Beschreibung
The co-nonsolvency behavior of the diblock copolymer (DBC) of PSBP-b-PNIPMAM has already been investigated, as well as the homopolymer of PSBP and PNIPMAM. However, the factors regulating the co-nonsolvency behavior are not only the solvent composition but also the anion series, which are not well studied yet in thin film geometry. In this project, we will study the specific ion effects on co-nonsolvency behavior of PNIPMAM and PSBP thin films following a recurring trend known as the Hofmeister series, which mainly includes the samples preparation via spin coating, thickness study via spectral reflectance and the polymer-water interaction study via Fourier transform infrared, as well as the surface morphology study via atomic force microscope. Besides, X-ray reflectometry will be used as a complementary method to analyze the migration or aggregation of salt molecules in the films. - Forschungsfeld
- Festkörperphysik (experimentell) (~50%)
- Materialphysik (experimentell) (~50%)
|
|
|
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)
|
|
|
Studying the spacial and kinematic properties of the particle emission in pp collisions at the LHC (Thema ist bereits vergeben) |
Fabbietti |
- Arbeitsgruppe
- Dichte und seltsame hadronische Materie
- Beschreibung
- In recent years, the method of femtoscopy has been successfully applied to make use of two-particle momentum correlations to investigate the strong force acting upon a pair of hadrons [Nature 588 (2020) 232-238]. This has been achieved by creating, at TUM, a numerical framework capable of modeling the pair-wise particle emission profile [Phys.Lett.B 811 (2020) 135849]. Nevertheless, the required input is model dependent, as it requires knowledge on the spacial and momentum correlations of the particles at the moment of their production.
The task of the participant is a continuation of the existing work, with the specific duty of studying the possibility of applying more generic methods to obtain information on the initial properties of the emission region. Finally, the bachelor candidate will implement the procedure within a universal framework, that is to be used in future N-body femtoscopic studies.
The requirements are:
1) Basic knowledge and interest in KTA.
2) Basic knowledge and interest in programming.
The gained experience is:
1) The basics of the statistical thermal model analysis of particle production at LHC.
2) Understanding of the femtoscopy method, with a stress on the particle emission in high-energy proton-proton collisions.
3) Working with numerical Monte-Carlo models.
4) Improvement of the programming skills, in particular C++ and the ROOT framework, both of which are essential in the field of data analysis. In addition, basic knowledge related to Python and Linux will be gained.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Dimitar Mihaylov
|
|
|
Suche nach geladenen Higgsbosonen mit dem ATLAS-Detektor am LHC (Thema ist bereits vergeben) |
Kortner |
- Arbeitsgruppe
- Hadronenstruktur und Fundamentale Symmetrien
- Beschreibung
- Mit der Entdeckung des Higgs-Bosons am CERN stellt sich die Frage, ob dies das einzige existierende Higgs-Teilchen ist. Viele Theorien jenseits des Standardmodels der Teilchenphysik sagen die Existenz zusätzlicher geladener Higgs-Teilchen voraus, die am Large Hadron Collider (LHC) produziert und durch ihre Zerfallsprodukte entdeckt werden könnten. Diese Bachelorarbeit sollte untersuchen, wie gut man die geladenen Higgs-Bosonen durch ihren Zerfall in einen Eichboson und ein schweres, elektrisch neutrales Higgs-Boson beobachten könnte. Dieser Zerfallsmodus wurde bisher noch nie mit dem ATLAS-Detektor untersucht.
- Forschungsfeld
- Teilchen und Felder (experimentell)
- Betreuer(innen)
- Oliver Kortner
|
|
|
Supramolekulare Selbst-Assemblierung photopolymerisierbarer Monolagen an fest-flüssig Grenzflächen |
Lackinger |
- Arbeitsgruppe
- Lehrstuhl für Wissenschaftskommunikation (Prof. Heckl)
- Beschreibung
- 2D Polymere sind neuartige, besonders vielseitige 2D Materialen, deren Synthese jedoch eine große Herausforderung darstellt. Besonders reguläre 2D Polymere können durch die topochemische Photopolymerisation auf Festkörper-Oberflächen hergestellt werden. Voraussetzung dafür ist die Selbst-Assemblierung der Monomere in geordnete, photoaktive Monolagen. Diesen Ansatz konnten wir für das Fantrip (fluoriniertes Anthracen-Triptycen) Monomer erfolgreich im Ultra-Hoch-Vakuum demonstrieren (Nat. Chem. 13, 730–736 (2021)).
Ziel der aktuellen Arbeit ist die Erforschung der Selbst-Assemblierung von Fantrip Monomeren an fest-flüssig Grenzflächen. Ein wesentlicher Vorteil dieser Variante liegt in der sehr einfachen Präparation. Weiterhin werden vorteilhafte Auswirkungen des dynamischen Gleichgewichts zwischen Desorption und Adsorption auf die Photopolymerisation erwartet.
Für die Präparation werden entsprechende Lösungen hergestellt, spektroskopisch charakterisiert und auf die Zieloberflächen pipettiert. Als Substrate werden graphitische Oberflächen verwendet, d.h. Graphit oder Mono- bzw. Bilagen-Graphen. Die Untersuchung der Monolagen erfolgt mittels hochauflösender Raster-Tunnel-Mikroskopie.
Diese experimentelle Arbeit ist in den Nanolaboren am Deutschen Museum angesiedelt.
- Forschungsfeld
- Oberflächenphysik (experimentell)
|
|
|
Synchrotron radiation and indirect detection of dark matter (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
Dark matter particles could annihilate in our galaxy, producing electrons in the final state. The electrons would swirl around the Milky Way's magnetic field, generating synchrotron radiation in the GHz range. This radiation could then be observed at Earth, thereby providing an “indirect” signature of dark matter's existence beyond its gravitational influence on astronomical objects. This bachelor thesis will analyze the properties of the synchrotron radiation produced in dark matter annihilations (emitted power, angular dependencies, frequency spectrum). As an application, we will consider the synchrotron radiation from the Smith's Cloud, which contains large amounts of dark matter and very little hydrogen, thus constituting an excellent target for dark matter detection. - Forschungsfeld
- Teilchen und Felder (Theorie)
|
|
|
Tests des Fireball Modells fuer Gamma-Ray Burst Afterglows |
Greiner |
- Arbeitsgruppe
- Max-Planck-Institut für extraterrestrische Physik (MPE)
- Beschreibung
- Gamma-ray bursts (GRBs) are flashes of gamma-ray resulting from the death of massive stars or the merger of neutron stars. They are followed by an `afterglow' signal that can be detected from radio to X-rays, produced by a shock wave moving into the gas surrounding the burster at approximately the speed of light. This afterglow light is well modelled with synchrotron emission, with the cooling frequency typically being close to the optical wavebands.
This thesis shall use a dataset of optical and X-ray data of 60 GRB afterglows and determine the location of the cooling break, and test the closure relations which exist between the spectral slope and the temporal decay slope. Technically, this involves (i) understanding optical and X-ray data, (ii) learn combined fitting of different instrument's data, (iii) understand synchrotron emission and the afterglow fireball modell, (iv) estimate uncertainties of the fit parameters, and (v) derive conclusions about the validity and limits of the model.
The project includes elements from computational and observational high-energy astrophysics, and will allow for obtaining extensive knowledge on gamma-ray bursts and related phenomena. 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)
|
|
|
The fate of the false vacuum: tunneling in quantum field theory (Thema ist bereits vergeben) |
Weiler |
- Arbeitsgruppe
- Theoretische Teilchenphysik an Collidern
- Beschreibung
- In quantum field theory, a false vacuum is a hypothetical vacuum that is relatively stable but not in the most stable state possible. This condition is known as metastable. It may last a very long time in that state but could eventually decay to a more stable state, an event known as false vacuum decay. The most common suggestion of how such a decay might happen in our universe is called bubble nucleation – if a small region of the universe by chance reaches a more stable vacuum, this "bubble" (also called "bounce") would spread.
The thesis aims to introduce tunneling in quantum mechanics using the WKB formalism, re-derive it with a path-integral approach using instantons, and then discuss the fate of the false vacuum in a simple quantum field theory system. The idea is to discuss the thin-wall limit analytically and develop a general solution either numerically or by using alternative expansions.
- Forschungsfeld
- Teilchen und Felder (Theorie)
|
|
|
The Inoculum Effect |
Gerland |
- Arbeitsgruppe
- Theorie komplexer Biosysteme
- Beschreibung
The “inoculum effect” is the phenomenon in which the population density of cells introduced to a new environment affects the time required for the cells to resume growth. Recent research in our group has indicated that several variables including culture temperature, prior starvation time and antioxidant concentration all affect the regrowth time of a culture following re-dilution. In this project, you will experimentally investigate how these variables affect regrowth time of E. coli in batch culture. As well as learning fundamental wet lab skills for the culturing of bacteria, you will also have the opportunity to theoretically analyze your results. No prior experience with experimental work is required – just an interest in biophysics and microbiology. - Forschungsfeld
- Biologische Physik (experimentell)
- Betreuer(innen)
- Zara Helen Gough
|
|
|
Theory and Phenomenology of Dark Matter Scattering off Electrons (Thema ist bereits vergeben) |
Ibarra |
- Arbeitsgruppe
- Theoretische Elementarteilchenphysik
- Beschreibung
In many well motivated scenarios, the dark matter particle interacts with the Standard Model, thus allowing to devise experiments for detecting novel dark matter signals (aside from gravitational) and ultimately for determining the properties of the dark matter particle (mass, spin, etc.). A promising strategy to search for dark matter is called “direct” search, in which a dark matter particle from the outer space enters a dedicated detector at the Earth and produces a visible signal. The most common approach in “direct” searches consists in searching for nuclear recoils induced by dark matter interactions with nuclei. However, the dark matter particle may interact predominantly with the leptons rather than with the hadrons, therefore new search strategies must be devised in order to probe this class of scenarios. In this bachelor thesis, it will be discussed the motivations for “leptophilic” dark matter scenarios, the possible production mechanisms in the early Universe, and the possibility of detecting the scattering of dark matter off electrons in current direct search experiments.
- Forschungsfeld
- Teilchen und Felder (Theorie)
|
|
|
Thin film material design for future magnonics |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Spin waves (magnons) are the quantized excitations of the magnetic lattice in solid state systems. The field of magnonics is exploring concepts to use these magnons for information transport and processing. Of special interest is to obtain reliable control over the relevant properties of these magnons such as, for example, their lifetime. The goal of your thesis is to fabricate high quality magnetically ordered thin film structures and investigate their spin wave properties via microwave spectroscopy methods.
You will gain experience in nanofabrication by working with state-of-the-art thin film deposition machines. Moreover, you will utilize thin film x-ray diffraction and magnetometry experiments to characterize the materials. You will utilize microwave spectroscopy techniques to extract the spin wave properties.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Matthias Opel
- Hans-Gregor Hübl
- Stephan Geprägs
|
|
|
Ultra-sensitive microwave spectroscopy setup for magnetic resonance |
Gross |
- Arbeitsgruppe
- Technische Physik
- Beschreibung
- Planar superconducting microwave resonators are key for the ultra-sensitive detection of spin properties. We employ planar microwave resonators fabricated from various superconducting materials like Nb, NbN and NbTiN and test their performance with respect to field and temperature stability. With your help, we aim to improve our resonators and test their performance with an existing variable temperature setup operating between 1.5 and 300K. You shall further asses the overall performance of the setup using magnetic resonance experiments.
Your bachelor thesis will bring you in touch with state-of-the-art microwave spectroscopy tools like vector network analyzers, as well as cryogenic measurement environments. In addition, you will fabricate and optimize microwave resonators and perform the microwave spectroscopy measurements. Moreover, the careful data analysis of the magnetic field dependent datasets will put you in the position, to make a meaningful impact on novel spin resonance spectroscopy approaches.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Matthias Althammer
- Hans-Gregor Hübl
|
|
|
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
|
|
|
Untersuchung des "Flachbandmagnetismus" in dem magnetischen Weyl-Halbmetall CoSnS |
Back |
- Arbeitsgruppe
- Experimentalphysik funktionaler Spinsysteme
- Beschreibung
- A recent scanning tunneling microscopy experiment (Nature Physics 15, 443 (2019))shows the existence of an orbital magnetic moment in the magnetic Weyl semimetal CoSnS. Such orbital magnetism originates from the kinetically frustrated Kagome flat band in this (and other) material and is purely a quantum mechanical effect. We expect that this orbital magnetic moment can be detected by the electron spin resonance technique, and the experimental results will be compared with theoretical calculations.
- Forschungsfeld
- Festkörperphysik (experimentell)
- Betreuer(innen)
- Lin Chen
|
|
|
Upgrade eines Raster-Tunnel-Mikroskops für Sub-Pikoampere Tunnelströme |
Lackinger |
- Arbeitsgruppe
- Lehrstuhl für Wissenschaftskommunikation (Prof. Heckl)
- Beschreibung
-
Die Abbildung empfindlicher Proben, wie beispielsweise schwach adsorbierende Moleküle mit komplexer nicht planarer Struktur, mittels Raster-Tunnel-Mikroskopie kann durch Wechselwirkungen zwischen Spitze und Probe beeinträchtigt werden. Eine mögliche Abhilfe besteht in der Vergrößerung des Spitze-Probe Abstands, die technisch durch verringerte Tunnelströme realisiert wird. Jedoch führt die Eingangskapazität längerer Signalleitungen zu hohem Eingangsrauschen bei den Tunnelstromverstärkern (Transimpedanzwandler), wodurch die Messbarkeit von Tunnelströme nach unten begrenzt wird. In der aktuellen Arbeit wird ein einfach aufgebauter Tunnelstromverstärker, bestehend aus einem Operationsverstärker, Rückkopplungswiderstand und stabilisierter Versorgungsspannung, in unmittelbarer Nähe der Probe installiert. Die Aufgabe besteht im Aufbau und der Inbetriebnahme des Tunnelstromverstärkers. Des weiteren sollen seine Grundcharakteristika, wie Signal-zu-Rausch Verhältnis und die verstärkungsabhängige Bandbreite sowie die Eignung für Raster-Tunnel-Mikroskopie experimentell bestimmt.
Diese experimentelle Arbeit ist in den Nanolaboren am Deutschen Museum angesiedelt.
- Forschungsfeld
- Oberflächenphysik (Theorie)
|
|
|
Vielteilchensysteme mit Zwangsbedingungen |
Knap |
|
|
|
|
Zugversuchsaufbau für die In-Situ-Positronenannihilationsspektroskopie (Thema ist bereits vergeben) |
Hugenschmidt |
- Arbeitsgruppe
- Neutronenstreuung
- Beschreibung
Tensile Testing is a fundamental materials science and engineering technique to study the strain hardening characteristics of metallic alloys. For a more in-depth investigation of atomic defects generated by the application of strain, we plan to combine tensile testing with the highly defect-sensitive spectroscopy of positron annihilation. In the course of this thesis, we expect the design and assembly of a tensile-test machine for in-situ positron annihilation spectroscopy. Finally, measurements on technical Al-alloys will help to understand proven techniques for metal hardening on an atomic level.
The project is carried out within the TUM research group Physics with Positrons. - Forschungsfeld
- Festkörperphysik (experimentell) (~60%)
- Materialphysik (experimentell) (~20%)
- interdisziplinäre Themen (experimentell) (~20%)
|
|
|
Zytoskelettäre Basis neuronaler Entwicklung |
Woehlke |
- Arbeitsgruppe
- Molekulare Biophysik
- Beschreibung
- Neuronen bilden im Laufe der Embryonalentwicklung ihre funktionalen Netzwerke aus. Bei der Regulation spielen Mikrotubuli und ihre Modifikationen eine wesentliche Rolle. In Kollaboration mit Dr. Monika Leischner (Neurozellbiologie, TUM Biederstein) sollen die quantitativen Zusammenhänge zwischen verschiedenen Regulatoren biophysikalisch untersucht werden.
- Forschungsfeld
- Biologische Physik (experimentell) (~80%)
- Biologische Physik (Theorie) (~20%)
|