Non-metallic, non-Fermi-liquid resistivity of FeCrAs from 0 to 17 GPa

TL;DR

This study reveals that FeCrAs exhibits a robust non-metallic resistivity that remains unchanged under high pressure, indicating an unconventional electronic state not driven by magnetic ordering or spin-density wave gaps.

Contribution

The paper demonstrates that the non-metallic resistivity of FeCrAs persists under pressures up to 17 GPa, challenging conventional explanations involving magnetic order or spin-density waves.

Findings

Non-metallic resistivity remains stable up to 17 GPa.

Antiferromagnetic order is suppressed with pressure.

Non-metallic behavior persists from 80 mK to 800 K.

Abstract

An unusual, non-metallic resistivity of the 111 iron-pnictide compound FeCrAs is shown to be relatively unchanged under pressures of up to 17 GPa. Combined with our previous finding that this non-metallic behaviour persists from at least 80 mK to 800 K, this shows that the non-metallic phase is exceptionally robust. Antiferromagnetic order, with a Neel temperature T_N ~ 125 K at ambient pressure, is suppressed at a rate of 7.1 +/- 0.1 K/GPa, falling to below 50 K at 10 GPa. We conclude that formation of a spin-density wave gap at T_N does not play an important role in the non-metallic resistivity of FeCrAs at low temperatures.