Spectroscopic and photorefractive characterization of cadmium telluride crystals codoped with vanadium and manganese

Abstract

Electron paramagnetic resonance spectroscopy, secondary-ion mass spectrometry, and moving space charge field techniques were used to characterize semi-insulating cadmium telluride crystals codoped with vanadium and manganese. Photorefractive two-wave-mixing gains were observed for CdTe:Mn,V that were a factor of \ensuremath{\sim}2 larger than that measured for singly doped CdTe:V. Secondary-ion mass spectrometry and electron paramagnetic resonance spectroscopy were used to establish the chemical identities, concentration levels, and charge states of the dopants that govern the photorefractive response in this semiconductor material. In CdTe:V,Mn only the ${\mathrm{Mn}}^{2+}$ EPR was observed; this result, combined with the photorefractive data, provides information regarding the existence of a manganese-related ionization level in the band gap of CdTe.