Abstract
This thesis reports on research that focuses on vanadium impurities in silicon carbide, and in particular on properties that are important for application as a qubit. Contrary to many other material systems, these impurities emit light in the near infrared coinciding with the telecom O-band, such that losses of such photons in optical fibers are relatively small. By using two-laser spectroscopy we studied the spin-relaxation dynamics in the ground state. By comparing the experimental results to a model, we derived that the decay of the nuclear spin is the slowest process. Next, we studied how the population difference between two states scan be increased. Depending on the temperature and the properties of the used laser light, we found that the population difference can be significantly improved. Another important property is the coherence time, as it forms the upper limit of the useful lifetime of a qubit. By using a combination of optical and microwave pulses we determined a lower limit for the coherence time of V defects. Furthermore, we observed that the V spin couples strongly to the nuclear spin of nearby isotopes. Finally, we fabricated SiC waveguides and demonstrated that light can be efficiently coupled in and stays confined to a small volume. This shows that these structures can be useful to enhance optical and electrical control over defects.
Original language | English |
---|---|
Qualification | Doctor of Philosophy |
Awarding Institution |
|
Supervisors/Advisors |
|
Award date | 31-May-2024 |
Place of Publication | [Groningen] |
Publisher | |
DOIs | |
Publication status | Published - 2024 |