An investigation was made of the optical properties of defects in Cd1-xZnxTe, where x ranged from 0 to 1. Residual impurities gave rise to far-infrared absorption, while metal vacancy-donor complexes (A centers), identified by means of optically detected magnetic resonance, were characterized by their near-infrared (1.4eV) photoluminescence. The zero phonon-line positions and phonon couplings were worked out for complexes which involved various group-VII (F, Cl, Br, In) or group-III (In, Al) donors. In addition to the A-center photoluminescence, 2 emission bands were found at 1.135 and 1.145eV. The temperature dependences of the photoluminescence showed that the 1.145eV luminescence followed the temperature dependence of the band gap, while the energy position of the 1.135eV emission shifted to higher energies with increasing temperature. The A-center photoluminescence, and the luminescence bands at 1.1eV, were investigated for x-values ranging from zero to unity. The A center and the 1.135eV band were found to follow the band-gap shift from CdTe to ZnTe, whereas the 1.145eV luminescence exhibited a constant emission energy.

W.Stadler, D.M.Hofmann, H.C.Alt, T.Muschik, B.K.Meyer, E.Weigel, G.Müller-Vogt, M.Salk, E.Rupp, K.W.Benz: Physical Review B, 1995, 51[16],10619-30