Optically detected electron-nuclear double resonance ofS=1 states of defects in semiconductors:PGa-YPin GaP

An optically detected electron-nuclear double resonance (ODENDOR) study of the phosphorus antisite-related defect ${\mathrm{P}}_{\mathrm{Ga}\mathrm{-}}$ ${\mathit{Y}}_{\mathrm{P}}$ in GaP is presented. Observed in an excited S=1 state via photoluminescence at ∼1.1 eV, it is established that the observed ODENDOR transitions arise from the ${\mathit{M}}_{\mathit{s}}$=0 state. The defect serves as a model to demonstrate the unusual features of ODENDOR spectroscopy in this state, for which there are no first-order magnetic hyperfine effects. By extending the analysis to second- and third-order perturbation, several of the important hyperfine parameters could be extracted.