The Pressure Effects on Electronic Structure of Iron Chalcogenide Superconductors FeSe$_{1-x}$Te$_x$

TL;DR

This study investigates how pressure influences the electronic structure and Fermi surface topology of FeSe$_{1-x}$Te$_x$ superconductors, revealing correlations with critical temperature changes and effects of tellurium substitution.

Contribution

It provides new insights into how pressure and tellurium substitution alter the Fermi surface, potentially affecting superconducting properties in iron chalcogenides.

Findings

Pressure reduces Fermi surface nesting between hole and electron pockets.

Tellurium substitution mimics pressure effects on the Fermi surface.

Fermi surface changes correlate with variations in critical temperature.

Abstract

We study the electronic structure of iron-based superconductors FeSe$_{1-x}$Te$_x$ within the density functional theory. We pay particular attention to the pressure effects on the Fermi surface (FS) topology, which seem to be correlated with a critical superconducting temperature TC of iron chalcogenides and pnictides. A reduction of the FS nesting between hole and electron cylinders with increasing pressure is observed, which can lead to higher values of TC . The tellurium substitution into selenium sites yields FS changes similar to the pressure effect.