Effect of sulfur doping on optical anisotropy of CdSiAs2

Abstract

Polarization dependent photoluminescence and photocurrent measurements were carried out on undoped and sulfur doped single crystals of CdSiAs2. For undoped crystal the interband transition A shows a 40 meV blueshift under perpendicular light polarization with respect to the parallel one. This shift is about twice as large for sulfur doped crystal. A pronounced photoabsorption band at 1.53 eV, related to the sulfur donor, is observed in the low temperature photocurrent spectrum. A significant enhancement of the optical anisotropy of donor-acceptor transition is seen in the low temperature photoluminescence spectra of CdSiAs2 doped with sulfur.