The effect of hydrostatic pressure and uniaxial strain on the electronic structure of Pb$_{\text{1-x}}$Sn$_{\text{x}}$Te

TL;DR

This study investigates how hydrostatic pressure and uniaxial strain influence the electronic band structure of Pb$_{1-x}$Sn$_{x}$Te, revealing tunable properties that could benefit spintronic device development.

Contribution

It demonstrates that strain and pressure can switch the band gap character in Pb$_{1-x}$Sn$_{x}$Te, offering a method to control its electronic properties for applications.

Findings

Pb$_{1-x}$Sn$_{x}$Te is a direct narrow-gap semiconductor for all x.

SnTe exhibits an inverted band structure near the Fermi energy.

Strain and pressure can tune the band gap from regular to inverted.

Abstract

The electronic structure of Pb$_{1-x}$Sn$_{x}$Te is studied by using the relativistic Korringa-Kohn-Rostoker Green function method in the framework of density functional theory. For all concentrations $x$, Pb$_{1-x}$Sn$_{x}$Te is a direct semiconductor with a narrow band gap. In contrast to pure lead telluride, tin telluride shows an inverted band characteristic close to the Fermi energy. It will be shown that this particular property can be tuned, first, by alloying PbTe and SnTe and, second, by applying hydrostatic pressure or uniaxial strain. Furthermore, the magnitude of strain needed to switch between the regular and inverted band gap can be tuned by the alloy composition. Thus, there is range of potential usage of Pb$_{1-x}$Sn$_{x}$Te for spintronic applications.