The thermoelectric transport properties of Bi2Te3/Sb2Te3superlattices are analyzed on the basis of first-principles calculations and semi-classical Boltzmann theory. The anisotropy of the thermoelectric transport under electron and hole-doping was studied in detail for different superlattice periods at changing temperature and charge carrier concentrations. A clear preference for thermoelectric transport under hole-doping, as well as for the in-plane transport direction was found for all superlattice periods. At hole-doping the electrical transport anisotropies remain bulk-like for all investigated systems, while under electron-doping quantum confinement leads to strong suppression of the cross-plane thermoelectric transport at several superlattice periods. In addition, insights on the Lorenz function, the electronic contribution to the thermal conductivity and the resulting figure of merit are given.
@article{arxiv.1206.4078,
title = {Thermoelectric transport in $\text{Bi}_2\text{Te}_3/\text{Sb}_2\text{Te}_3$ superlattices},
author = {N. F. Hinsche and B. Yu. Yavorsky and M. Gradhand and M. Czerner and M. Winkler and J. König and H. Böttner and I. Mertig and P. Zahn},
journal= {arXiv preprint arXiv:1206.4078},
year = {2012}
}