Stabilization of Ambient Pressure Rocksalt Crystal Structure and High Critical Field Superconductivity in ReC via Mo and W Substitution

TL;DR

This paper reports the synthesis of ReC with stabilized rocksalt structure at ambient pressure through Mo and W substitution, revealing high-field superconductivity and expanding the class of ultra-hard superconducting materials.

Contribution

It introduces a novel method to stabilize ReC in a rocksalt structure at ambient pressure and demonstrates its high critical field superconductivity with Mo and W doping.

Findings

ReC with Mo/W substitution exhibits type-II, fully gapped superconductivity.

The compounds have high critical magnetic fields.

They are among the new ultra-hard superconducting materials at ambient pressure.

Abstract

Transition-metal-based carbides (TMCs), renowned for their exceptional hardness, mechanical strength, and thermal properties, have recently emerged as promising candidates for topological superconductivity. In this study, we synthesized ReC in the NaCl structure at ambient pressure by substituting Mo or W at the Re-site. We investigated the superconducting properties of Re$_{1-x}$T$_{x}$C (where T = Mo, W) for $x = 0.5$ using magnetization, resistivity and specific heat measurements. These compounds display type-II, fully gapped, weakly coupled superconductivity with high critical fields, establishing them as new members of superconducting ultra-hard materials at ambient pressure and paving the way for superconducting device applications under extreme conditions.