Defect structure of Bi2−xAsxTe3 single crystals

Single crystals Bi2−xAsxTe3 were prepared by a modified Bridgman technique. The samples were characterized by X-ray diffraction analyses and measurement of Hall coefficient and electrical conductivity. Atomic absorption spectroscopy (AAS) was used for determination of actual content of As in the samples. The doping of Bi2Te3 with As leads to a decrease of the free carriers concentration while their mobility increases. The observed effects are discussed within a point defect model of Bi2−xAsxTe3 crystals.