Calculation of figure of merit for Bi$_2$Te$_3$ nanostructures

Bi$_2$Te$_3$-based materials comprise one class of promising candidates for novel thermoelectric devices, for which low/high thermal/electrical conductivity are desired. We shall present calculations highlighting the effects of reduced dimensionality on the thermoelectric figure of merit ZT for such materials, with particular emphasis on Bi$_2$Te$_3$ / Sb$_2$Te$_3$ superlattices. The calculation consists of two components, a tight-binding electronic calculation for the electrical conductivity and electronic contribution to the thermal conductivity and a Green-Kubo molecular dynamics approach for the lattice contribution to the thermal conductivity.