Electron Spin Resonance of N₁-Center in Diamond

Abstract

Temperature dependence of N₁-center, a deep donor nitrogen in diamond, is investigated. A clear change in the hyperfine structure of the center is observed around 680 K. The result, explained by the model, is that the self-trapped state with uniaxial symmetry which is stable at low temperatures changes to an isotropic donor state above 680 K.