Optical and electrical studies of vapour phase grown Cd1−xCoxTe crystals

The optical properties of vapour phase grown crystals of diluted magnetic semiconductor (DMS) Cd1−xCoxTe were investigated for x = 0.001, 0.003, 0.005, 0.007 and 0.009. The reflectivity spectra exhibited a regular shift in the fundamental absorption edge (E0) with composition x. The reflectivity spectra for the present samples of Cd1−xCoxTe of all compositions exhibit broad bands at 5300 and 11,100 cm−1 due to the transitions of 4A2 → 4T1 (F) and 4A2 → 4T1 (P), respectively. Temperature dependence of resistivity revealed semiconducting behaviour of the samples. Hot probe test revealed that all the samples exhibited p-type conductivity.