Work Function of Bismuth Telluride: First-Principles Approach

TL;DR

This paper presents a first-principles computational method to accurately determine the work function of Bi2Te3 (0001) surface using density functional theory and many-body perturbation theory, providing a reliable prediction of its electronic properties.

Contribution

It introduces a combined approach using DFT and GOWO perturbation theory to calculate the work function of Bi2Te3 from first principles, which is novel for this material.

Findings

Work function of Bi2Te3 (0001) surface is predicted as 5.301 - 5.131 eV.

Method accurately aligns bulk band edges with vacuum energy levels.

Results are compared with other elements to contextualize the work function.

Abstract

First-principles approach is demonstrated to calculate the work function of Bi2Te3. The reference potential and the vacuum energy levels are extracted from the Bi2Te3 (0001) surface structure using the reference potential method based on the density functional theory. The one-shot GOWO many-body perturbation theory is used to place the bulk band edge energies with respect to the reference level and the vacuum energy. At last, the work function of 5.301 - 5.131 eV is predicted for Bi2Te3 (0001) surface and compared to various elements.