B.Sc. and M.Sc. Projects

 

Experimental Simulation and Modelling Theory

 

Experimental

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Additionally to the advertised projects, we are always very happy about unsolicited applications. Please contact the principal investigator who you want to work with to discuss possible projects.

  Neural net Copyright: Otten

B.Sc. Project Machine Learning techniques for automated tuning of quantum dots

In this project, you will research and implement machine-learning techniques to identify certain features in a measured set of charge stability diagrams and classify the data by the number of quantum dots. The goal of this project is not only to implement first machine learning approaches and use them for automated tuning, but also to establish this knowledge in our group.

Project description (PDF)

  Typical spectra of an InAs quantum dot Copyright: Kardynal

B.Sc.-Project Dark-field microscopy for resonant excitation of self-assembled quantum dots

In this project, you will develop dark-field optical microscopy setup based on polarization optics. You will use it to characterise properties of the InAs quantum dots under resonant excitation. To achieve this goal you will add the polarization optics in the existing micro-photoluminescence setup and develop an algorithm to align it for a maximum signal to background ratio.

Project description (PDF)

  GaAs sample Copyright: Cerfontaine

M.Sc. Project Experimental High-Fidelity Two-Qubit Gates for Spin Qubits

In this project you will work on the experimental demonstration and characterization of a two-qubit gate mediated by the exchange interaction. Using a sophisticated 15 mK measurement setup, you will control two qubits with advanced high-frequency control and readout electronics.

Project description (PDF) Contact: Pascal Cerfontaine

  Optical cavity Copyright: Witzens

M.Sc. Project: Time Multiplexed Optical Qubit Readout

In this project, you will be designing optical cavities to facilitate the collection of photons emitted by quantum dots into optical fibers. This project is part of a new activity initiated by the Chair of Integrated Photonics (IPH) together with the Quantum Technology Group on time-interleaved (multiplexed) optical readout of quantum dots.

Project description (PDF)

  Si-MOS device Copyright: Klos

M.Sc. Project Multi qubit Si quantum devices fabricated by industrial processes

In this project, you will fabricate and characterize the Si-MOS quantum device with state-of-the art equipment at IHT and our group. This explicitly includes the hands-on improvement and use of industrial fabrication processes in multiple research cleanroom facilities in Aachen and electrical measurements in our low temperature setups and cryostats.
Project description (PDF)

  GaAs device Copyright: Liu

M.Sc. Project The development of an optically-active gate-defined quantum dot

In this project, you will build an optical setup to conduct a systematic characterization of a new type of optically-active gate-defined quantum dot. Such quantum dot can be used to create an optical interface between flying photonic qubits and stationary spin qubits, which is a building block for quantum Internet.

Project description (PDF)

  Chevron pattern Copyright: Struck

M.Sc.-Project High fidelity manipulation and detection of a qubit in silicon

In this project you will optimise the control and read-out of a spin qubit in silicon. You will learn working with a sophisticated low-temperature measurement set-up. You will confine single electrons in a quantum dot, manipulate the electron spin by electric dipole spin resonance and improve the qubit control

Project description (PDF) Contact: Lars Schreiber

  Silicon qubit Copyright: Veldhorst et al., Nature 526, 410-414 (2015)

M.Sc. Project Characterization of silicon qubit devices fabricated on 300 mm wafers

In this project you will characterize and improve industrially manufactured MOS-type two qubit devices. These devices facilitate higher fabrication throughput and reproducibility. You will learn how to tune Si qubit devices in order to form quantum dots and gain experience in low temperature measurements at 10 mK, high frequency, low noise measurement and data analysis using python and matlab.
Project description (PDF) Contact: Lars Schreiber

  GaAs sample Copyright: Otten

M.Sc. Project 3D Integration of Semiconductor Based Spin-Qubits

In this project, you will develop a flip chip process for a 42 qubit device. Large qubit numbers require a high contact density and tight integration with control hardware, both of which can benefit from modern assembly processes. Flip-Chip bonding is a well-established in industry process and will be developed for quantum chips in this project.

Project description (PDF)

  Scanning electron micrograph of the silicon QuBus Copyright: Seidler

M.Sc.-Project Fabrication and characterization of a quantum-bus in silicon

In this project you will fabricate and characterize a single electron spin quantum bus using cutting-edge ebeam lithography at HNF (FZ Jülich) and 10 mK electronic tranport measurements at IQI, RWTH. As a first step the functionality of the single-electron charge detector at the end of the QuBus and the gate isolation is tested before single electrons can be transported.

Project description (PDF) Contact: Lars Schreiber

  Schematic of a ZnSe double quantum dot Copyright: Schreiber

M.Sc.-Project Towards electron spin quantum bits in ZnSe

ZnSe exhibits ideal properties for hosting electron spin quantum bits. However, this II/VI semiconductor has not been considered for this purpose. In close collaboration with the group of Alex Pawlis (FZ Jülich), who is an expert in the growth of (Zn,Mg)Se heterostructures, you will electrically characterize (Zn,Mg)Se heterostructures using 1K electrical transport experiments.
Project description (PDF) Contact: Lars Schreiber

 


 

Simulation and Modelling

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Additionally to the advertised projects, we are always very happy about unsolicited applications. Please contact the principal investigator who you want to work with to discuss possible projects.

 


 

Theory

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Please find a couple of examples of theoretical projects below. However, we always consider unsolicited applications. Please contact the principal investigator with whom you want to work to discuss possible projects.

  Damped harmonic oscillator Copyright: Lisa Arndt

B.Sc. Project Radiation of the harmonic oscillator

In this project, you will analyse and simulate a quantum harmonic oscillator that is coupled to external modes, e.g., a LC-resonator coupled to a transmission line. The coupling can annihilate excitations in the harmonic oscillator by moving the energy in the transmission line where it appears as radiation. This effectively leads to dissipation. By employing various methods, you will study the time-evolution of the system. Another important research topic is to characterize the radiation that is emitted in the external mode.
Contacts: , Fabian Hassler

  Shapiro setup Copyright: Lisa Arndt

B.Sc. Project Quantum noise and dual Shapiro steps

In this thesis, you will explore the influence of quantum noise on the height of the dual Shapiro steps. You will start by simulating a classical system of a driven phase-slip junction in the presence of dissipation. Next, you will add quantum noise to the classical Langevin equation and analyse how the additional noise influences the height of the dual Shapiro steps.
Contacts: , Fabian Hassler

  Detector setup Copyright: Fabian Hassler

M.Sc. Project Detector theory for m icrowave photonics with superconducting quantum circuits

In superconducting quantum systems, a significant part of the emitted microwave radiation can be collected and converted to an amplified output signal. This allows for a detailed study of the correlations of the radiation. The statistics of the radiation can offer a valuable insight into the quantum nature of the radiation. It demonstrates phenomena like squeezing or multi-photon processes. In order to study such phenomena theoretically, it is necessary to develop a fitting model for the detector. The goal of this project will be to explore different theoretical detector models for microwave photonics, including the initial detection of the photons, the amplification of the signal, and possible backaction due to the detector.
Contacts: , Fabian Hassler

  Hall bar Copyright: David DiVincenzo

B.Sc. Project

Hall Effect Gyrator

This work will continue recent investigations in our group on the action of an essential component in quantum microwave science, the gyrator. Here you will do calculations of the real-time propagation of electromagnetic fields in this device. Contact: David DiVincenzo

  Qubit-Heterostructure Copyright: Pascal Cerfontaine

B.Sc. Project Improved Quantum Dot Qubits

In this project you will explore theoretically variants of the semiconductor quantum dot to perform quantum gate fidelity and readout. There will be an emphasis on tailoring the spin-orbit action to achieve optimal performance, and on varying the electron number and confinement strength. Contact: David DiVincenzo

  Flux Qubit Copyright: Gianluigi Catelani

B.Sc. and M.Sc. Projects Superconducting Qubits

In these projects you will study theoretically some basic properties (energy levels, wave functions, matrix elements) of superconducting qubits such as the fluxonium and the flux qubit. These properties can be accurately calculated numerically in most cases, especially if the problem reduces to that of a quantum particle in a one-dimensional potential. The goal here is to construct an approximate but accurate analytical solution to such a quantum-mechanical problem, using perturbation theory, the WKB approximation, etc. For a B.Sc. project, a symmetric double-well potential will be analyzed. Extension of the results to asymmetric potentials, and to two- or three-dimensional problems, can be considered for a M.Sc. project. Contact: Gianluigi Catelani (g.catelani@fz-juelich.de)