Features of the charge-transport mechanism in layered Bi2Te3 single crystals doped with chlorine and terbium

The temperature dependences (T = 5−300 K) of the resistivity in the plane of layers and in the direction perpendicular to the layers, as well as the Hall effect and the magnetoresistance (H < 80 kOe, T = 0.5−4.2 K) in Bi2Te3 single crystals doped with chlorine and terbium, are investigated. It is shown that the doping of Bi2Te3 with terbium atoms results in p-type conductivity and in increasing hole concentration. The doping of Bi2Te3 with chlorine atoms modifies also the character of its conductivity instead of changing only the type from p to n. In the temperature dependence of the resistivity in the direction perpendicular to layers, a portion arises with the activation conductivity caused by the hopping between localized states. The charge-transport mechanism in Bi2Te3 single crystals doped with chlorine is proposed.