Pressure-induced magnetic collapse and metallization of $\mathrm{TlF}{\mathrm{e}}_{1.6}\mathrm{S}{\mathrm{e}}_{2}$

TL;DR

This study investigates how high pressure affects TlFe1.6Se2, revealing a transition from an antiferromagnetic semiconductor to a metallic state with potential superconductivity around 7 GPa.

Contribution

It provides new insights into pressure-induced magnetic collapse and metallization in TlFe1.6Se2, highlighting possible superconductivity near magnetic transition.

Findings

Insulator-to-metal transition at ~7 GPa

Loss of magnetic order at the transition

Possible onset of superconductivity below 15 K

Abstract

The crystal structure, magnetic ordering, and electrical resistivity of TlFe1.6Se2 were studied at high pressures. Below ~7 GPa, TlFe1.6Se2 is an antiferromagnetically ordered semiconductor with a ThCr2Si2-type structure. The insulator-to-metal transformation observed at a pressure of ~ 7 GPa is accompanied by a loss of magnetic ordering and an isostructural phase transition. In the pressure range ~ 7.5 - 11 GPa a remarkable downturn in resistivity, which resembles a superconducting transition, is observed below 15 K. We discuss this feature as the possible onset of superconductivity originating from a phase separation in a small fraction of the sample in the vicinity of the magnetic transition.