Electron paramagnetic resonance studies of silicon-related defects in diamond

Abstract

We report the results of multifrequency electron paramagnetic resonance studies at temperatures between 8 and 300 K on diamonds synthesized by chemical vapor deposition and intentionally silicon doped with isotopes in natural abundance or isotopically enriched. The $^{29}\text{S}\text{i}$ hyperfine structure has provided definitive evidence for the involvement of silicon in two electron paramagnetic resonance centers in diamond that were previously suspected to involve silicon: KUL1 and KUL3. We present data that unambiguously identify KUL1 as an $S=1$ neutral silicon split-vacancy (${D}_{3d}$ symmetry) defect ${(V\text{-Si-}V)}^{0}$, while KUL3 is shown to be ${(V\text{-Si-}V)}^{0}$ decorated with a hydrogen atom, ${(V\text{-Si-}V:\text{H})}^{0}$.