Evidence for near-infrared photoluminescence of nitrogen vacancy centers in4H-SiC

Abstract

We present evidence of near-infrared photoluminescence (PL) signature of nitrogen vacancy centers (NCVSi)− in silicon carbide (SiC). This center exhibits an S=1 ground state spin similar to the NV− center in diamond. We have performed photoluminescence excitation measurements at cryogenic temperature and demonstrated efficient photoexcitation of distinct photoluminescence from (NCVSi)− in 4H-SiC. Furthermore, by correlating the energies of measured zero phonon lines (ZPLs) with theoretical values derived from hybrid density functional theory each of the ZPLs has been associated to the respective occupation of hexagonal (h) and quasicubic (k) lattice sites in close analogy to neutral divacancy centers (VCVSi)0 in the same material. Finally, with the appropriate choice of excitation energy we demonstrated the selective excitation of (NCVSi)− PL with no contamination by (VCVSi)0 PL, thereby opening the way towards the optical detection of (NCVSi)− electron spin resonance.