Enhancement of the Thermoelectric Figure of Merit in Gated Bismuth Telluride Nanowires

摘要

We theoretically studied how the electric filed effect can modify thermoelectric properties of intrinsic bismuth telluride nanowires, which are grown along [110] direction. The electronic structure and wave functions were calculated by solving the self-consistent system of the Schrodinger and Poisson equations by means of both the Thomas-Fermi approximation and the spectral element method. The thermoelectric parameters were determined using a constant relaxation-time approximation. The external electric field can increase the Seebeck coefficient of a nanowire with 7-15nm lateral dimensions by nearly a factor of two, and enhance the figure of merit by an order of magnitude.