Silicon vacancy-related centers in non-irradiated 6H-SiC nanostructure

We present the first findings of the silicon vacancy related centers identified in the non-irradiated 6H-SiC nanostructure using the electron spin resonance (ESR) and electrically-detected (ED) ESR technique. This planar 6H-SiC nanostructure represents the ultra-narrow $p$-type quantum well confined by the $\delta$-barriers heavily doped with boron on the surface of the $n$-type 6H-SiC (0001) wafer. The new EDESR technique by measuring the only magnetoresistance of the 6H-SiC nanostructure under the high frequency generation from the $\delta$-barriers appears to allow the identification of the isolated silicon vacancy centers as well as the triplet center with spin state $S$ = 1. The same triplet center that is characterized by the large value of the zero-field splitting constant $D$ and anisotropic $g$-factor is revealed by the ESR (X-band) method. The hyperfine (HF) lines in the ESR and EDESR spectra originating from the HF interaction with the $^{14}$N nucleus seem to attribute this triplet center to the N-V$_{\mathrm{Si}}$ defect.