Effects of van der Waals interactions and quasiparticle corrections on the electronic and transport properties of Bi2Te3

TL;DR

This paper investigates how van der Waals interactions and quasiparticle corrections influence the structural, electronic, and transport properties of Bi2Te3, achieving results consistent with experimental data through advanced first-principles calculations.

Contribution

It demonstrates the importance of including vdW interactions and GW corrections for accurate modeling of Bi2Te3's properties, providing a comprehensive theoretical analysis.

Findings

OptB86b-vdW reproduces experimental lattice constants.

GW calculations accurately predict band structure and transport properties.

Calculated thermoelectric coefficients match experimental measurements.

Abstract

We present a theoretical study of the structural, electronic and transport properties of bulk Bi2Te3 within density functional theory taking into account the van der Waals interactions (vdW) and the quasiparticle self-energy corrections. It is found that the optB86b-vdW functional can well reproduce the experimental lattice constants and interlayer distances for Bi2Te3. Based on the fully optimized structure, the band structure of Bi2Te3 is obtained from first-principles calculations with the GW approximation and the Wannier function interpolation method. The global band extrema are found to be off the high-symmetry lines, and the real energy band calculated is in good agreement with that measured experimentally. In combination with the Boltzmann theory, the GW calculations also give accurate prediction of the transport properties, and the calculated thermoelectric coefficients of Bi2Te3 almost coincide with the experimental data.