Theses and Internships
We are always happy to welcome students, either for a reasearch internship or a Bachelor/Master thesis. At the moment we can offer the following projects:
Master thesis/Research internship: Dynamical Decoupling pulse sequences for the generation of heralded entanglement between color centers in 4H silicon carbide
Supervision: Maximilian Hollendonner
To generate a quantum internet of things, multiple quantum memory nodes which are mutually entangled with each other, are needed. At the institute of Applied Quantum Technologies (AQuT.) we aim at entangling two silicon vacancy centers in 4H silicon carbide. These centers serve as the central building blocks which mediate the entanglement between various entities of the quantum network. Hereby pulse sequences are needed, which simultaneously protect the vacancy against dephasing and thus maintain the entangled state between the two color centers.
Within the research internship/ master thesis, pulse sequence will be developed which simultaneously allow for the generation of heralded entanglement and also protect the vacancy’s against dephasing.
Supervisor: Maximilian Hollendonner – maximilian.hollendonner@fau.de
Start: Immediately
Bachelor thesis: Temperature control of magnets for Zeeman splitting of silicon vacancy centers in 4H silicon carbide
Supervision: Maximilian Hollendonner
To use silicon vacancy centers in 4H silicon carbide for quantum computing applications, it is necessary to apply static magnetic fields which cause Zeeman splittings of the vacancy’s eigenstates. As the magnetic field of permanent magnets can change due to, for instance, temperature fluctuations, it is necessary to stabilize these magnetic fields. Through quantum sensing methods, the magnetic field generated by the permanent magnets can be measured via the silicon vacancy. These results can then be used for feedback loops which control the effective magnetic field of the magnet.
During the bachelor thesis, a feedback loop which stabilizes the magnetic field will be implemented. Hereby it will be necessary to understand the interplay between fluctuations of temperature and magnetic fields as measured via the silicon vacancy centers and to implement control strategies against these fluctuations.
Supervisor: Maximilian Hollendonner – maximilian.hollendonner@fau.de
Start: Immediately
Bachelor/Master thesis: Light propagation in doped silicon carbide waveguides
Combining the spin qubit system of SiC together with its excellent electronic properties offers several opportunities for as platfrom for integrated quantum nanophotonics. This thesis is about simulating a photonic waveguide structure consiting of differently doped SiC layers. How do different parameters affect the optimal waveguiding of the light emitted by the SiC color center?
Supervisor: Daniel Scheller – daniel.scheller@fau.de
Start: Immediately
Master thesis: Process development for etching free-standing waveguide structures in silicon carbide
RIE-ICP Farady etching is a technique commonly used to etch free-standing triangular shaped waveguides in diamond and silicon carbide. In this thesis includes the design and fabrication of a Faraday cage, first test device fabrication and analysing the influence of different parameters like the cage desing or etching parameters.
Supervisor: Daniel Scheller – daniel.scheller@fau.de
Start: Immediately
Master thesis: Sensor head for NV-center based quantum magnetography
You will plan, design, and construct the optics of a sensor head for NV-center based quantum magnetography and put this sensor to use. You will learn about the measurement of magnetic fields with nitrogen vacancy centers in diamond and after constructing the sensor head you will be able to measure magnetic fields with NV centers yourself, for example the magnetic fields caused by smartphones.
During the thesis you will conduct the following work:
- Design of the sensor head
- Optical simulation of the sensor head with Ansys Zemax
- Construction of the sensor head in the lab
- Performing magnetic field measurements with the sensor
Preparatory knowledge (recommended but not necessary):
- Basics of quantum technologies and quantum sensing
- Good optics/photonics background is definitely helpful
- Zemax (optical simulation software)
Supervisor: Johannes Wesseler – johannes.wesseler@fau.de
Start: Immediately
Bachelor thesis/ research internship: Environmental factors for portable magnetic sensors based on NV centers in diamond
In this project you will investigate if and how environmental factors like humidity, pressure, temperature, and stray fields influence a portable magnetic sensor based on NV center in diamond. You will learn about the measurement of magnetic fields using nitrogen vacancy centers in diamond and will use a magnetic field sensor based on these lattice defects yourself. Possible environmental influences that we could investigate are: Influence of air pressure, influence of humidity, influence of stray fields (e.g. WLAN router), influences of vibrations. During the thesis you will conduct the following work:
- Optical simulation of environmental influences on the sensorhead (Zemax)
- Testing the sensorhead in the lab
- Measuring magnetic fields with the sensorhead
- Performing magnetic field measurements with the sensor
Preparatory knowledge (recommended but not necessary):
- Basics of quantum technologies and quantum sensing
- Good optics/photonics and HF background
- Zemax (optical simulation software)
Supervisor: Johannes Wesseler – johannes.wesseler@fau.de
Start: Immediately
Bachelor thesis/ research internship/ Master thesis: Design of resonators for the control of nuclear spins in SiC
As part of the research performed at the Institute of Applied Quantum Technologies (AQuT.), we are working on the electromagnetic and optical control of color centers in Silicon Carbide (SiC). Hereby we aim at realizing a quantum memory via the nuclear spins of 13C and 29Si.
To efficiently control nuclear spins at cryogenic temperatures, a frequency-matched and temperature controlled solution for the incoupling of AC magnetic fields is necessary, which can be realized through a coil, specifically designed for the environment within the cryostat.
During the thesis the following points should be adressed:
- Simulation of magnetic fields for various geometries within our experimental setting
- Simulaiton of the thermic flux
- Optimization of the coil and its manufacturing
- Measurements and optimization of the coil
The work packages can be adressed in different thesis.
Beneficial knowledge (not strictly necessary):
- COMSOL
- Basics of Quantum Technologies
- Basics of HF
Supervisor: Fedor Hrunski – fedor.hrunski@fau.de
Start: Immediately