Thesis defence F. Lüthi: quantum electrodynamics

25 March 2019 10:00 - Location: Aula, TU Delft - By: webredactie

Circuit quantum Electrodynamics in a Magnetic Field. Promotor 1: Prof.dr. L. Di Carlo (TNW); Promotor 2: Prof.dr.ir. L.P. Kouwenhoven (TNW).

Quantum computers promise to solve certain problems much more efficiently than their classical counterparts. The massive parallelization that will be enabled with quantum computers will help simulating chemical processes much faster than using classical computers, and will help to develop drugs and catalysts. Next to the yet unknown uses, further applications of interest are shortest-path optimizations, weather forecasting and material research. 

There are many different possible ways to implementing a quantum computer, and it is not clear yet which material platform will ultimately lead to a working quantum computer. One particularly promising candidate system is based on superconductors . The performance of a quantum computer crucially relies on its fundamental building block, the quantum bit, or short qubit. As these qubits are still imperfect it is important to understand the factors limiting them. For superconducting qubits, one of these limitations is flux noise. The microscopic origin of flux noise is still unknown.

My long-term research topic therefore is to investigate this noise process in ways that were previously not possible– by applying a magnetic field. In order to achieve this, a new type of superconducting qubit was used which is based on semiconducting nanowires. Precise characterisations of such devices lead to detailed insights of their workings. Using their field compatibility and the improvements of the stability of the setup will allow us to understand the process of flux noise better. Detailed knowledge of its microscopic origin will help defining fabrication procedures that avoid flux noise, and therefore lead to better quantum computers. 

More information?

For access to theses by the PhD students you can have a look in TU Delft Repository, the digital storage of publications of TU Delft. Theses will be available within a few weeks after the actual thesis defence.