Optically detected magnetic-resonance observation of spin-dependent interdefect electron transfer in the GaP:(V,S) system

Abstract

A strong, optically detected magnetic-resonance (ODMR) signal at g=1.99 is observed on the internal ${}_{}{}^3{}_{}{}^{}$ ${\mathit{T}}_2$ ${\to }^3$ ${\mathit{A}}_2$ emission of ${\mathrm{V}}^{3+}$. The ODMR excitation spectrum is identical with the emission spectrum. From the analysis of the experimental data it is nevertheless concluded that the spin resonance does not arise from the V but is due to shallow S donors present in the sample. A model accounting for the spin-dependent electron-transfer mechanism is suggested. An unidentified photoluminescence emission centered at 1.35 eV with an isotropic g=2.06 ODMR line is also observed.