Composition-dependent charge transport and temperature-dependent density of state effective mass interpreted by temperature-normalized Pisarenko plot in Bi_2−<i>x</i>Sb_<i>x</i>Te₃ compounds

Abstract

Composition-dependent charge transport and temperature-dependent density of state effective mass-dependent Seebeck coefficient were investigated in Bi2−xSbxTe3 (x = 1.56-1.68) compounds. The compounds were prepared by the spark plasma sintering of high-energy ball-milled powder. High-temperature Hall measurements revealed that the charge transport in the compounds was governed dominantly by phonon scattering and influenced additionally by alloy scattering depending on the amount of Sb. Contrary effects of Sb content on the Seebeck coefficient were discussed in terms of carrier concentration and density of state effective mass, and it was elucidated by temperature-normalized Pisarenko plot for the first time.