Pressure-enhanced superconductivity in quasi-1D cobalt carbide Sc₃CoC₄

National Laboratory of Solid State Microstructures and Department of Physics, Center for Superconducting Physics and Materials, National Center of Microstructures and Quantum Manipulation, Nanjing University Nanjing 210093, China

^(a) xiyuzhu@nju.edu.cn (corresponding author)
^(b) hhwen@nju.edu.cn (corresponding author)

Received: 14 April 2016
Accepted: 26 July 2016

Abstract

We have successfully synthesized the quasi-1D cobalt carbide Sc₃CoC₄ by using the arc-melting technique which is similar to that of the previous reports. An incomplete superconducting transition is detected at ambient pressure. In addition, two anomalies have been observed at 72 K and 143 K both from resistivity and magnetic susceptibility measurements. According to previous studies, it was argued that they correspond to the 1D Peierls-type distortion and charge-density-wave transitions, respectively. By applying a pressure, the transition at about 72 K is quickly suppressed, which is accompanied by the occurrence of a complete superconducting transition at about 4.5 K. Moreover, the DC magnetic susceptibility under high pressures also reveals the enhancement of superconductivity. We attribute this enhancement of superconductivity to the suppression of the Peierls-type distortion at about 72 K and probably together with the promoted Josephson coupling between the [CoC₄]_∞ one-dimensional ribbons.