Theoretical investigation of FeTe magnetic ordering under hydrostatic pressure

TL;DR

This study uses density functional theory to explore how hydrostatic pressure affects the structural and magnetic phases of FeTe, revealing pressure-induced magnetic transitions and the suppression of magnetism around 17 GPa, which may explain the absence of superconductivity.

Contribution

It provides a detailed theoretical prediction of FeTe's pressure-dependent structural and magnetic phase diagram, including the identification of various magnetic phases and their transitions.

Findings

Magnetic order changes with pressure, including ferromagnetic phases.

Magnetism is suppressed around 17 GPa.

Absence of superconductivity linked to magnetic behavior.

Abstract

We investigate the pressure phase diagram of FeTe, predicting structural and magnetic properties in the normal state at zero temperature within density functional theory (DFT). We carefully examined several possible different crystal structures over a pressure range up to $\approx 30 $ GPa: simple tetragonal (PbO type), simple monoclinic, orthorhombic (MnP type), hexagonal (NiAs and wurzite type) and cubic (CsCl and NaCl type). We predict pressure to drive the system through different magnetic ordering (notably also some ferromagnetic phases) eventually suppressing magnetism at around 17GPa. We speculate the ferromagnetic order to be the reason for the absence of a superconducting phase in FeTe at variance with the case of FeSe.