PGa-antisite-related neutral complex defect in GaP studied with optically detected magnetic resonance

A triplet (S=1) spectrum for a deep PGa-antisite-related complex defect in (Cu,Li)-codoped GaP has been studied with optical detection of magnetic resonance. The defect has a 110 orientation, and a hyperfine interaction in agreement with PGa is clearly resolved, although the magnitude of the A tensor is considerably reduced compared to the isolated PGa defect. The electronic structure of the defect is consistent with a strongly localized electron-hole pair, recombining radiatively at a neutral defect, suggested to be a PGa-CuGa pair. The anisotropic behavior of the g tensor (and in part the D tensor) is explained as mainly due to a residual spin-orbit interaction of the bound hole.