Possible superconductivity in Bismuth (111) bilayers. Its electronic and vibrational properties from first principles

TL;DR

This study uses first-principles calculations to explore the electronic, vibrational, and potential superconducting properties of bismuth (111) bilayers, revealing metallic behavior and estimating a transition temperature around 2.61 K.

Contribution

First-principles analysis of bismuth (111) bilayers' electronic and vibrational properties, suggesting possible superconductivity with a specific transition temperature.

Findings

Electronic density of states shows metallic character.

Vibrational density of states exhibits a layer-induced gap.

Estimated superconducting transition temperature is approximately 2.61 K.

Abstract

Using a 72-atom supercell we report ab initio calculations of the electronic and vibrational densities of states for the bismuth (111) bilayers (bismuthene) with periodic boundary conditions and a vacuum of 5 {\AA}, 10 {\AA} and 20 {\AA}. We find that the electronic density of states shows a metallic character at the Fermi level and that the vibrational density of states manifests the expected gap due to the layers. Our results indicate that a vacuum down to 5 {\AA} does not affect the electronic and vibrational structures noticeably. A comparison of present results with those obtained for the Wyckoff structure is displayed. Assuming that the Cooper pairing potential is similar for all phases and structures of bismuth, an estimate of the superconducting transition temperature gives 2.61 K for the bismuth bilayers.