zur Hauptseite

Peter Grünberg Institute

Navigation und Service

Bachelor thesis: Characterizing the quantum mechanical transport properties in topological insulator compounds of different stoichiometric

Jan 23rd, 2020

About topological insulators

In 2016, the Nobel prize of physics was awarded to the “theoretical discoveries of topological phase transitions and topological phases of matter”. Today this phase of matter is investigated from an experimental point of view. Practical applications for the materials predicted are promising: Not only are they prospective candidates for the building blocks of novel spintronic devices, they are also supposed to host Majorana zero modes which are the fundament of a new concept for robust quantum computation. In the PGI-9 we fabricate these materials and in our state of the art cleanroom in the Helmholtz Nano Facility we build nano-scale devices out of these by applying industrial relevant methods. Their quantum transport properties are characterized at temperatures close to absolute zero. We probe the materials using ultra small currents, inducing superconductivity into these materials and creating quantum
superposition states.

TI phase coherent loopsTI phase coherent loops
Copyright: Jonas Kölzer

Project Description:

This project focuses on the software package QCoDeS being used in order to perform measurements. The idea is to be able to measure nanostructures fully automated.

What you will learn:

You will learn to operate measurements in a state of the art programmable framework called QCoDeS. It is a Python-based data acquisition framework developed by the Copenhagen / Delft / Sydney / Microsoft quantum computing consortium. The goal is a common framework for physics experiments, so:
- new students don’t need to spend a long time learning software, in order to participate in experiments
- one has to write their own code only for pieces that are very specific to their own experiment
- code can and should be contributed back to the framework
- the process of moving between teams or labs, and of setting up a new experiment is streamlined
- physics experiments can take advantage of modern software and best practices

The central tasks that have to be done are:
1. automate a standard magnetoconductance measurement on a nanostructure
2. build a feedback mechanism that optimizes the measurement parameters while measuring
3. analyze the data with respect to different quantum mechanical phenomena

Prof. Dr. Thomas Schäpers
Peter Grünberg Institut PGI-9, Gebäude 02.11, Raum 105
Tel.Nr.: +49 (0)2461 61 2668