Topological transition in Pb1-xSnxSe using Meta-GGA

TL;DR

This study investigates the topological phase transition in Pb1-xSnxSe alloys by calculating the mirror Chern number and band gap using advanced density functional theory methods, providing insights into the material's topological properties.

Contribution

The paper demonstrates the effectiveness of the modified Becke-Johnson meta-GGA functional with specific parameters in accurately predicting topological transitions in Pb1-xSnxSe.

Findings

Results align with experimental data for MCN and band gap.

Modified Becke-Johnson functional with c=1.10 accurately describes the topological transition.

Provides a computational approach for studying topological phase changes in similar materials.

Abstract

We calculate the mirror Chern number (MCN) and the band gap for the alloy Pb1-xSnxSe as a function of the concentration x by using virtual crystalline approximation. We use the electronic structure from the relativistic density functional theory calculations in the Generalized-Gradient- Approximation (GGA) and meta-GGA approximation. Using the modified Becke-Johnson meta- GGA functional, our results are comparable with the available experimental data for the MCN as well as for the band gap. We advise to use modified Becke-Johnson approximation with the parameter c=1.10 to describe the transition from trivial to topological phase for this class of compounds.