Optically Driven Charge State Switching of SiC Defects

Defects have been identified in silicon carbide (SiC) with long spin coherence times and electronic structures similar to the diamond nitrogen vacancy (NV), but in a host material that may be more conducive to future wafer-scale quantum technologies. We focus on divacancies and NVs in 4H-SiC which have optical transitions ranging from 1070 nm to 1240 nm, closer to telecom wavelengths. We use photoluminescence excitation measurements of divacancy ensembles to investigate an energy dependent suppression and recovery of the fluorescence, observing a threshold energy of about 1.3 eV that varies for different divacancy types. We attribute these effects to optically driven switching between different charge states [1]. Additionally we explore NVs in SiC, taking the first steps towards microwave and optical control of single defect spins.
[1] D. A. Golter and C. W. Lai, Sci. Rep. 7, 13406 (2017).