All-optical coherent population trapping with defect spin ensembles in   silicon carbide
  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. 
Olger V. Zwier, Danny O'Shea, Alexander R. Onur, Caspar H. van der Wal
cond-mat.mes-hall cond-mat.mtrl-sci quant-ph