Screened exchange LDA determination of the ground and excited state properties of thermoelectrics: Bi2Te3

摘要: Predicting the performance of thermoelectric materials requires precise knowledge Fermi surface and near-lying electronic structures. While ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$ is a major constituent active layers in commercial coolers, ab initio structure theory heretofore has failed to reproduce measured experimental band gap. Herein, we report self-consistent screened-exchange local density approximation (sX-LDA) calculations for ${\mathrm{Bi}}_{2}{\mathrm{Te}}_{3}$, using full-potential linearized augmented plane-wave method including spin-orbit coupling. Our results include (i) predicted sX-LDA gap $154\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$, excellent agreement with zero temperature extrapolated value $162\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$; this may be compared previously reported LDA generalized gradient values 61 $50\phantom{\rule{0.3em}{0ex}}\mathrm{meV}$, respectively; (ii) significant improvement effective masses electrons, respect experiments previous calculations.