Disputation: Marianne Etzelmüller Bathen

Doctoral candidate Marianne Etzelmüller Bathen at the Department of Physics, Faculty of Mathematics and Natural Sciences, is defending the thesis 

"Point defects in silicon carbide for quantum technologies: Identification, tuning and control"

for the degree of Philosophiae Doctor.

portrait of the candidate

The PhD defence and trial lecture are fully digital and streamed using Zoom.  The chair of the defence will moderate the disputation.

Ex auditorio questions: the chair of the defence will invite the audience to ask ex auditorio questions either written or oral. This can be requested by clicking 'Participants' and then choose 'Raise hand'. 


Trial lecture

"Quantum computer architectures; quantum gates versus adiabatic solutions"



Main research findings

Quantum technology offers enticing capabilities such as secure communication, nanoscale sensing and novel quantum computers of potentially extreme power. However, current platforms for these technologies are based on superconducting materials, and require millikelvin temperatures to function.

In this work, we explore the potential of point defects in semiconductors as quantum contenders. Removing a silicon atom from the silicon carbide lattice creates a Si vacancy. The Si vacancy emits single photons on-demand, and has a long-lived spin state that can be used to implement quantum bits. Herein, concepts related to formation, identification, control and transformation of the Si vacancy and related defects are investigated.

This thesis shows how we can control the charge state and emission energy of Si vacancies by exposure to laser light, strain and electric fields. Furthermore, heat treatments may cause the transformation of Si vacancies into various defect complexes, leaving mainly the carbon vacancy behind. Different transformation and migration pathways for Si and C vacancies in SiC are explored, and are relevant for both quantum and power electronics applications.


Contact information to Department: Line Trosterud Resvold

Published Nov. 20, 2020 12:51 PM - Last modified Dec. 5, 2020 2:47 PM