First-Principles Study on Electronic, Mechanical and Thermoelectric Transport Properties of Topological Insulator NaAuS

摘要

We have investigated the mechanical, electronic and thermoelectric transport properties of material using density functional theory. Our calculated results predict that NaAuS is elastically and thermodynamically stable material. We have calculated band gap of 0.15eV for this material using PBE functional including spin-orbit coupling (SOC). Band inversion at gamma point indicates about the topological behavior of material. The calculated value of power factor and Seebeck Coefficient is 8.874x10~(11) W/msK~2 and 140.42 μV/K, respectively; at T=1000K. Lattice thermal conductivity which plays a significant role in thermoelectric efficiency of a material, is found to be 5.62 W/mK at T=300K. The lattice thermal conductivity of this material decreases with increase in temperature. The figure of merit (ZT) comes out to be 0.79 at T=1000K, thus this material can act as good thermoelectric material.