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arXiv · 1411.1366

All-optical coherent population trapping with defect spin ensembles in silicon carbide

Olger V. Zwier·Danny O'Shea·Alexander R. Onur·Caspar H. van der Wal
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Abstract

Divacancy defects in silicon carbide have long-lived electronic spin states and sharp optical transitions, with properties that are similar to the nitrogen-vacancy defect in diamond. We report experiments on 4H-SiC that investigate all-optical addressing of spin states with the zero-phonon-line transitions. Our magneto-spectroscopy results identify the spin $S=1$ structure of the ground and excited state, and a role for decay via intersystem crossing. We use these results for demonstrating coherent population trapping of spin states with divacancy ensembles that have particular orientations in the SiC crystal.

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Olger V. Zwier, Danny O'Shea, Alexander R. Onur, Caspar H. van der Wal. 2014-11-05. All-optical coherent population trapping with defect spin ensembles in silicon carbide. https://doi.org/10.1038/srep10931

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