Stabilization of ambient pressure rocksalt crystal structure and high critical field superconductivity in ReC via Mo and W substitution

Abstract Transition-metal-based carbides, 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 substituting Mo ( x = 0.1, 0.2, 0.4, 0.5, 0.6, 0.8, 0.9) or W ( x = 0.2, 0.5, 0.8) 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.