Effect of strain and many-body corrections on the band inversions and topology of bismuth

TL;DR

This paper investigates how strain and many-body corrections influence the band structure and topological properties of bismuth, using advanced electronic structure calculations to understand the delicate state ordering at the L point.

Contribution

It provides a detailed analysis of the impact of strain and many-body effects on bismuth's band inversions and topology, highlighting their importance in topological characterization.

Findings

Strain significantly alters the band ordering at the L point.

Many-body corrections affect the topological nature of bismuth.

Structural parameters are crucial for accurate topological predictions.

Abstract

The electronic band structure of Bi is calculated using state of the art electronic structure methods, including density functional theory and G$_0$W$_0$ quasiparticle approximations. The delicate ordering of states at the L point of the Brillouin zone, which determines the topological character of the electronic bands, is investigated in detail. The effect on the bands of strain, changing the structural parameters of the rhombohedral crystal structure, is shown to be important in determining this ordering and the resulting topological character.