Theoretical Study of Electronic Structures of Bi2Te3/Sb2Te3 Superlattices

Abstract

ABSTRACTTo understand thermoelectric properties of multiplayer Bi2Te3/Sb2Te3 superlattices, especially their charge transport properties, electronic structure calculations were carried out using ab-initio gradient corrected density functional theory. The superlattice structures of (1,1) and (1,2) Bi2Te3/Sb2Te3 multilayers were optimized and their band structures were compared with each other. Different lattice relaxation effects are observed for the two structures. The cross-plane and inplane effective masses for both these systems are found to be comparable, consistent with experimental mobility measurements.