Our ab initio simulations determined the magneto-optical properties of the neutral divacancy in silicon carbide that contributed to understanding its qubit operation carried out by Prof. David D. Awschalom group.
Phys. Rev. X 7, 021046 (2017). DOI:10.1103/PhysRevX.7.021046
Our ab initio study identified the nitrogen terminated (111) diamond surface to host shallow nitrogen-vacancy centers for quantum sensing. In cooperation with Alex Retzker we showed, that special quantum simulations can be carried out with the nitrogen nuclear spins in this system
Nano Letters 17 (4), pp 2294-2298. (2017) DOI:10.1021/acs.nanolett.6b05023
We investigated the electron-phonon coupling in small diamond cages called diamondoids. These quantum systems are mostly modelled within the Born-Oppenheimer approximations, where the coupling between the electrons and vibration modes is not fully taken into account. In our study we shown that the severe electron-phonon coupling is a key point to properly describe the overall lineshape of the experimental photoemission spectrum. Our method goes beyond the typical Born-Oppenheimer approximation, where the electrons are pure electron-like quasi-particles. In our model, we deduced a link between the many-body perturbation approach of the electron-phonon coupling and the well-known Jahn-Teller effect.
Nature Communications 7: 11327. (2016). DOI:10.1038/ncomms11327
The chemical vapor deposition of diamond is known to introduce complexes of silicon, vacancy, and hydrogen. We theoretically examined several such complexes, some of which have already been observed, others which could potentially form. Using hybrid density functional theory for the treatment of highly correlated orbitals, many measurable quantities are calculated. The SiV2H(-) negatively charged defect is found to be a promising candidate for a long lived solid state quantum memory. The study is highlighted as Editor's suggestion in PRB.
Phys. Rev. B 92 165203 (2015). DOI:10.1103/PhysRevB.92.165203
In collaboration with German (Jörg Wrachtrup group at Stuttgart University) and Swedish (Erik Janzén group at Linköping University) researchers, we report the characterization of photoluminescence and optical spin polarization from single silicon vacancies in SiC, and demonstrate that single spins can be addressed at room temperature. We show coherent control of a single defect spin and find long spin coherence times under ambient conditions. Our study provides evidence that SiC is a promising system for atomic-scale spintronics and quantum technology. Our study is highlighted in a News and Views article from Nature Materials.
Nature Materials 14 164-168 (2015). DOI:10.1038/nmat4145