As of 1.10.2022, the Faculty of Physics has been merged into the TUM School of Natural Sciences
with the website https://www.nat.tum.de/.
For more information read
Conversion of Websites.
The advanced lab course offers the opportunity to undertake complex physics experiments in our research institutes already during your Bachelor’s and Master’s studies.
This page describes the advanced lab courses in the B.Sc. Physics as well as in the Physics Master programs and in the M.Sc. Quantum Science & Technology. Information on the advanced lab course in the M.Sc. Biomedical Engineering and Medical Physics can be found on the specific pages of the BEMP advanced lab course.
The experiments in the Advanced Lab Course are integrated into the experimental groups at the Physics Department and the participating Max-Planck institutes, where they are carried out. In addition LMU provides selected experiments exklusively for the students in M. Sc. Quantum Scinece & Technology. It is the ideal opportunity to learn a bit more about the research done in each place and to gain important information regarding the future specialization or the choice of the Bachelor's/Master's thesis.
Overall responsibility for the Advanced Lab Course is with Prof. Sharp and Prof. Schönert for the Physics programs and Prof. Brandt for the M. Sc. Quantum Science & Technology.
Safety Instruction
A safety instruction is obligatory for each participant before taking part at the advanced lab course and then at least once a year. The safety instruction including a test is done in an online Moodle course.
Registration for the Advanced Lab Course
Registration for the Advanced Lab Course is done via TUMonline. Exception is experiment 61 – you can find information on the registration at the experiment below.
Finding a Team
The experiments in the Advanced Lab Course are done in teams of regularly three students. If sufficient places are available, as an exception an experiment can be done by two students. The experiments at LMU, exclusively available for students in M. Sc. Quantum Science & Technology, are also done in teams of three.
Ideally you find your team at the beginning of the semester. It makes sense, when the team members have similar interests and hence are enroled in the same study program. To support you in finding a team you can use the FOPRA channel in the TUM Chat.
Select a name for your team (it is helpful to simply concatenate your three lastnames together). This team has to be entered at registration by every team member.
We recommend that you work as a team for the semester. But technically it is possible to register in different registration procedures/two-week periods with a different team.
Experiment Selection
Get together with your team before registering in TUMonline and select the experiments and time slots possible for all of you.
Keep in mind that not all experiments are offered in every time slot. You can find out in which timeslots an experiment is offered by selecting the course in TUMonline – the course detail page lists all the registration procedures and hence the timeslots the course is offered in.
Notes on experiment selection for specific programs:
Bachelor’s program Physics
Within the Bachelor's program course 6 CP have to be achieved from the FOPRA. To orientate oneself in all scientific directions, there are no restrictions concerning the attribution of the experiments to certain major fields of study KM, KTA, BIO or AEP. Experiments exclusive to the QST cannot be included in the Bachelor studies.
Due to the restrictions that apply in the Master’s programs it even makes sense to select experiments complementary to your own focus area.
Since the FOPRA takes place during the winter and the summer semester we recommend to perform 4 experiments during the winter and 2 experiments during the summer semester.
Masters’s program Physics (KM, KTA, BIO, AEP)
Within one of the Master' programs 6 CP have to be achieved from the FOPRA. In doing so at least four CP must originate from the elected major field of study (KM, KTA, BIO, AEP).
We recommend to perform three experiments in the winter semester and three experiments in the summer semester. Experiments that are only assigned to QST as well as experiments already used in the TUM Bachelor can not be taken.
Masters’s program QST
Within the Master's program QST 6 CP have to be achieved from the FOPRA. In doing so at least two credits must be earned from each of the two focus areas (experimental/theory). The assignment to the respective focus area can be seen in the table with the experiments (Ex = experimental / TH = theory).
We recommend to do the FOPRA in your second semester (SS).
Masters’s program Science Education (MA/PH teacher)
Within the Master's program in science education (mathematics / physics) 4 CP in FOPRA have to be achieved. There are no restrictions concerning the attribution of the experiments to certain major fields of study. Only the LMU experiments are exklusive only for QST students.
Registration in TUMonline
There is a registration period for each two-week period during the lecture period in TUMonline.
In each registration procedure with a time slot suitable for you give your preferences for all of the experiments you want to do. You will finally be assigned at most one place. If you give preferences for an experiment in more than one time slots you will at most be assigned one place in this experiment.
Each team member needs to register in TUMonline!
All team members give the same team namen (e. g. simply concatenating your three lastnames together)!
All team members in one registration procedure select the same experiments!
The electronics lab (experiments 90/91) consists of weekly dates that need to be attended during all of the semester. Registration for the Electronics Lab Course is done in a separate registration procedure.
Direct Links to the registration procedures:
W 20/21 (experiments still available: 5, 23, 24, 43, 104)
W 16/17 (experiments still available: 5, 23, 33, 37, 108)
W 14/15 (experiments still available: 23, 33, 37, 45, 107, 113)
W 18/19 (experiments still available: 5, 23, 24, 32, 37, 39, 104, 108)
W 22/23 (experiments still available: 5, 23, 24, 33, 34, 37, 38, 45, 104, 107, 108, 113)
W 24/25 (experiments still available: 5, 15, 23, 33, 37, 45, 104, 108, 113)
W 26/27 (experiments still available: 5, 15, 23, 24, 33, 37, 45, 104, 107, 108, 113)
W 28/29 (experiments still available: 5, 15, 23, 24, 37, 45, 104, 107, 108, 113)
W 30/31 (experiments still available: 5, 15, 23, 24, 33, 37, 45, 104, 107, 108, 113)
W 32/33 (experiments still available: 5, 15, 23, 24, 33, 37, 45, 104, 107, 108, 113)
W 34/35 (experiments still available: 5, 15, 23, 24, 37, 45, 104, 107, 108, 113)
W 36/37 (experiments still available: 5, 15, 23, 24, 33, 37, 45, 104, 107, 108, 113)
W 38/39 (experiments still available: 5, 15, 23, 24, 33, 37, 45, 104, 107, 108, 113)
Assignment of Places
Assignment of places is done asynchroneously according to the default ranking – keep in mind that the registration date has no influence on your ranking until the next assignment date. Places are only assigned if at least two students with the same team name register for the same experiment and the same date. Teams of three are preferred to teams of two.
The first places for the winter term 2022/23 were assigned on the 21st of October 2022. Until the end of the term you still may add further preferences for experiments in future timeslots. Remaining places are assigned each Friday.
In TUMonline your status can reach three levels:
"requirements met" means, that you have applied for a place at this experiment in the given timeslot.
"distributed" means, that a place in the given timeslot would be available for you. This is the status that you get directly after the new FOPRA lottery on friday, if your team won a slot. If you stay in this status you most probably did not pass the test to the safety instruction in Moodle. In this case: please repeat the test until you get all 9 answers right. If you cannot register in the Moodle course, please write an E-Mail to studium@ph.tum.de .
"confirmed place" means that your team should now contact the experiment’s supervisors and obtain the individual dates for conducting the experiment.
If you are assigned a confirmed place you are automatically informed by TUMonline via E-Mail. As a team contact the experiment’s supervisors, if you were assigned a confirmed place, in order to obtain the individual dates for conducting the experiment.
On-Campus and Online Labs
Due to the restrictions of corona pandemic some of the lab experiments take place in pure online mode without presence of students. Besides this some other experiments there exists the possibility that only one part of the group participates in presence, the other group member(s) is (are) connected by videoconference. This has to be discussed individually with the corresponding experiment supervisor.
Doing the Experiment
For the realisation of the experimental part, one has to plan an entire day – which occasionally can only happen at the expenses of other courses. The complete realisation of a FOPRA experiment includes:
Preparation (insufficiently prepared participants may be rejected)
Experimental realization
Working out (written)
Colloquium (minimum 30 minutes long, final discussion and examination)
The Advanced Lab Course is defined as course work, which is a pass/fail scheme without numerical total grade. For some experiments numerical grades are issued. These are only for your self-assessment and are printed on grade reports only not on the final Transcript of Records.
Each successfully completed experiment will be entered by the corresponding supervisors in TUMonline as passed exam. Every participant is asked to check that her/his entry in TUMonline is done promptly after finishing the experiment. Check with the experiment’s supervisors if something is missing.
You will perform a low temperature experiment at liquid helium temperature (4.2 K) to investigate a superconducting tunnel junction - a so-called Josephson junction - consisting of two Nb 100 nm thick electrodes separated by a thin aluminium oxide (AlOx) layer (about 17 nm thick). The junction area is a square with an edge length L of about 20 μm. Josephson junction feature a finite supercurrent (Josephson current) through the tunneling barrier at zero voltage drop between the two junction electrodes. You will measure the maximum Josephson current I_c by recording the IV-characteristics of the junction. The zero-voltage Josephson current across a Josephson junction is proportional to the sine of the phase difference varphi of the macroscopic wave functions describing the two superconducting junction electrodes: I_s = I_c sin(varphi). This phase difference is modified by a magnetic field applied parallel to the tunneling barrier. This results in a characteristic magnetic field dependence of the maximum Josephson current, corresponding to the diffraction pattern of a slit in optics. You will record this pattern and derive the Josephson penetration depth from the period of the pattern. From the experiment you will get basic insights into the phasics of Josephson junctions and in techniques used to perform low temperature experiments.
How fast can information propagate through a quantum many-body system with local interactions? Lieb-Robinson bounds provide fundamental upper limits on the speed at which the dynamics of such a system can distribute initially localized information. In particular, these bounds give a “speed limit” called the Lieb-Robinson velocity.Applications of Lieb-Robinson bounds are numerous; including multi-dimensional Lieb-Schultz-Mattis theorems, exponential clustering in gapped ground states, area laws, the analysis of quantum phases of matter, the complexity of states and many, many more.In this project, you will learn how to formalize the question of information propagation in terms of basic quantum-mechanical concepts such as Heisenberg-evolved operators and operator norms of commutators. Following a list of instructions, you will then develop a mathematicalproof of this fundamental result.As applications you may consider consequences of Lieb-Robinson bounds to the problem of state preparation or to topological order.In the first application you will show that certain highly entangled states such as the GHZ-state cannot be generated by a locally generated unitary in constant time from a product state.This result can also be reinterpreted a circuit depth lower bound on preparation circuits and thus immediately connects to complexity-theoretic questions in quantum computing.Another application concerns Kitaev’s toric code, a local stabilizer Hamiltonian on a 2D lattice of qubits whose ground states satisfy a condition called topological quantum order (TQO): no local observable can distinguish orthogonal ground states. While TQO is immediately connected to quantum error correction via the so-called Knill-Laflamme conditions, here you will study another key consequence of TQO derived from Lieb-Robinson bounds: preparing ground states of the toric code from a product state using locally generated unitary evolution requires a time scaling at least linearly in the (linear) system size.Overall, this project will help familiarize yourself with a fundamental tool in quantum many-body systems and basic results in topological order.
In the standard (circuit) model of quantum computation, a typical computation proceeds by application of an n-qubit unitary U to a certain initial state and subsequent measurement of each qubit in the computational basis. The hardware of a universal quantum computer should therefore provide the capability of applying an arbitrary unitary U. In practice, however, control of quantum systems is severely limited by the specifics of the system under consideration and/or experimental limitations. For example, control pulses (realizing unitary evolutions) may only be applied along a certain subset of directions with a restricted range of frequencies and/or durations. Is such hardware su cient to reach the desired goal of performing universal quantum computation? If so, how many operations are required to realize a given unitary U?In this project, you will be given a (ficticious) device that implements a single-qubit unitary specified by a discrete set of control parameter values. Your task is to use (several copies of) this device to (approximately) realize an arbitrary n-qubit unitary U. In other words, you will generate an instruction set (a quantum circuit) for executing the corresponding quantum computation using the given hardware.A key notion of interest here is that of a universal gate set, a finite family of (typically single- and two-qubit) unitaries (called gates) such that any unitary U can be approximately written as a product of a certain number L of gates. Given such a universal gate set, we may ask about the relationship between the length L of the gate sequence (ultimately corresponding to the runtime of your computation) and the quality of approximation. In addition, we want to efficiently (by classical computation) find a suitable sequence. The so-called Solovay-Kitaev theorem provides answersto this problem and is the main topic of this project. The project will involve a collection of mathematical exercises. You will also gain experience programming in python by developing and implementing a compilation procedure as described above.
Entanglement is a fundamental resource in quantum information that features in many well-known protocols (e.g., teleportation). Therefore, it is of interest to understand which evolutions of quantum systems preserve or destroy this resource. In this project, you will investigate so-called entanglement-breaking maps, i.e., maps that for any input state produce a separable output. You will focus on physical situations where the interactions between an open system under consideration and its environment are weak so that the dynamics can be well described by a Markovian evolution. In mathematical terms, this means that you will study (continuous) semigroups of quantum channels.In this project, you will first learn about basic properties of the objects of interest (i.e., entanglement-breaking channels and semigroups of channels) by solving a collection of mathematical exercises. Once you are familiar with these notions and after some technical preparation, you will be guided through the proof of the following equivalence, which is the main goal of the project: An evolution described by a semigroup of quantum channels becomes entanglement-breaking after some finite time if and only if every initial state converges to a unique full-rank invariant state.Your task will be to provide the details for the steps of the proof based on the instructions given. In doing so, you will encounter techniques from di↵erent areas relevant to quantum information, e.g., linear algebra and spectral theory. In particular, you will have an opportunity to apply what you have learned in the lecture on “Introduction to Quantum Information Processing”. This will give you a better understanding of the structure of the set of separable states, of the behaviour of Markovian quantum evolutions, and it will bring you closer to the current research about these questions.
Semidefinite Programming in Quantum Information Theory
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The need to optimize arises frequently in everyday live. What is the fastest route from A to B? What is the cheapest hotel in Munich that provides breakfast and is at most 5 kilometers away from Marienplatz? When engineering quantum devices, the broad question that arises over and over again is how to best perform a certain information processing task given the experimental constraints at hand. Convex optimization techniques (and especially semidefinite programs (SDPs)) have proven to be a vital tool to compute the answer to these questions e ciently. In this project, you will be introduced to SDPs by putting on the hat of a quantum engineer who tries to design devices that peform the following three tasks.1. Suppose your friend challenges you with the following game: He will prepare a quantum system described by one of the (mixed) states rho1, rho2, . . . , rhoN. You have to guess which state it is. If you guess correctly, he will pay for the next barbeque and otherwise you have to pay. What is the best way to measure the system to maximize your chances of guessing right?2. You have another friend who studies abroad. When she left, she gave you a part of her most beautiful quantum system (which we know to be in state rhoAB) to stay connected. The next time you talk to her, she tells you that studying abroad has changed her mind about the beauty of quantum states completely and that she now likes the pure state the most. Unfortunately, she did not bring any quantum equipment with her so she asks you to perform a quantum operation on your part of the system such that the overall state is as close as possible to her beloved state phi. How would you choose that quantum operation to make her as happy as possible?3. A few childhood friends of yours like to play with Boolean functions. As an introduction to their game they want you to guess which function they are currently playing with. You choose an input, and ask them for some information on the output. For each piece of information they give you, you have to pay some amount of money, and since you do not want to end up being poor, you need to guess the function as soon as possible. How could you do that?In this project, you will learn how to formulate these problems mathematically as an SDP and how to solve such an SDP with Matlab using the cvx package.
Quantum mechanical systems exhibit fundamentally different properties compared to classical systems. While the state of a classical particle can at any time be described by a set of well defined classical variables, quantum particles can be in superposition of different sates. If two or more particles are in a superposition such that the full state of the system can only be described by a joint superposition, then these particles are called entangled. The question whether the behaviour of entangled systems is determined by classical (local, realistic) variables was posed in a well-known paper in 1935 by Albert Einstein, Boris Podolsky, and Nathan Rosen (collectively “EPR”). Later, Bell formulated an inequality which allows to experimentally test whether the behaviour of entangled particles can be explained using such classical variables.Besides these fundamental physics questions, entanglement is the key element for applications of quantum physics such as quantum cryptography, teleportation or quantum computation. Furthermore, its characteristics can be used for a fundamental test of non-classical properties of quantum theory. Quantum tomography is an essential tool for many of these applications. In this lab course we will perform quantum state tomography on polarization-entangled photon pairs and violate Bell’s inequality.
In superconducting quantum circuits, such as quantum bits, information is processed and transferred in the form of microwave quantum signals. Moreover, at the end of quantum information protocols, these signals have to be recorded by room temperature electronic devices. Since microwave quantum signals typically consist of very few photons, they must be amplified in order to achieve reasonable signal-to-noise ratios. Therefore, low-noise amplification of quantum signals is crucial. Modern low-noise microwave amplifiers are built upon superconducting Josephson parametric devices, such as a flux-driven Josephson Parametric Amplifier (JPA), which allows to reach the standard quantum limit of amplification and even go beyond it. The current JPA is formed by a superconducting quantum interference device (SQUID) combined with a superconducting coplanar waveguide resonator. The combined system acts as a tunable nonlinear microwave resonator, whose frequency can be varied in-situ via an external magnetic field. A mechanical analogue would be a pendulum of variable length, allowing one to tune its eigenfrequency. Tunability of the nonlinear microwave resonator can be exploited to parametrically pump the JPA via application of a strong microwave signal at twice the resonant frequency. This, in turn, can result in a strong parametric amplification of weak quantum signals incident at the JPA. The same parametric amplification mechanism can be exploited further for generation of genuine quantum signals in the form of squeezed vacuum states.
Your contact data will be imported automatically from TUMonline. So please pay attention that your phone number ist registered in TUMonline and that you get the messages to the email address which is deposited in your TUMonline account. Changes of supervisors at your experiment should be reported to study@ph.tum.de.