Negatively charged Si vacancy in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mn>4</mml:mn><mml:mi>H</mml:mi></mml:math>SiC: A comparison between theory and experiment

Abstract

We use electron paramagnetic resonance and electron nuclear double resonance to identify the negatively charged Si vacancy in neutron-irradiated $4H$ SiC. The identification is based on resolved ligand hyperfine interactions with carbon and silicon nearest and next nearest neighbors and on the determination of the spin state, which is $S=3/2.$ The magnetic resonance parameters of ${V}_{\mathrm{Si}}^{\ensuremath{-}}$ are almost identical for the polytypes $3C,$ $4H,$ and $6H.$ The experimental findings are supported by theoretical ligand hyperfine interaction data based on a total-energy calculation using the standard local-density approximation of the density-functional theory.