The optical properties of Cd1-xMnxTe (0 < x < 0.55) solid solutions in monocrystals and thin polycrystalline films

The optical absorption spectra at the fundamental absorption edge of Cd1-xMnxTe (0 <= x <= 0.5) at 78-300 K have been Studied. Single crystals were grown by Bridgman method. At 293 K, the fundamental absorption red edge in crystals with x <= 0.5 is determined by the exciton absorption. The fundamental absorption edge has the specific shape of crystals with high impurity levels density. The absorption spectra in the domain of the fundamental absorption band of Cd1-xMnxTe solid solutions in thin films prepared by discrete ("flash") evaporation of synthesized single crystals and by physical vapor deposition (using Cd0.5Mn0.5Te as source material) are investigated. The optical gap of Cd1-xMnxTe films prepared by discrete evaporation is equal to similar to 2.0 eV and 2.13 eV at temperatures 293 K and 78 K, respectively. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim