Optical absorption and electron paramagnetic resonance of in GaP

Abstract

The results of optical absorption, electrical conductivity, and electron paramagnetic resonance (EPR) experiments on different p-type GaP:V:Zn samples are reported. The transition of gives rise to a broad triple-peaked absorption band and a zero-phonon line (ZPL) at . These features are explained as due to a strong Jahn-Teller coupling of the state. The reduced spin-orbit splitting is smaller than the strain-broadened line-width of the ZPL. The EPR spectrum of , which is angular dependent at T < 4 K, is analysed (g = 1.960, ). Its intensity shows dependence on microwave power characteristics for an impurity with an ground state. The photo-induced recharging is monitored by optical absorption as well as EPR and requires the recharging of anti-site defects.