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arXiv · 2302.06612

Topological transition in Pb1-xSnxSe using Meta-GGA

Rajibul Islam·Giuseppe Cuono·Nguyen M. Nguyen·Canio Noce·Carmine Autieri
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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.

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Rajibul Islam, Giuseppe Cuono, Nguyen M. Nguyen, Canio Noce, Carmine Autieri. 2023-02-13. Topological transition in Pb1-xSnxSe using Meta-GGA. https://doi.org/10.12693/aphyspola.136.667

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