Superconductivity in the cobalt-doped V3Si A15 intermetallic compound

TL;DR

This study investigates the superconducting properties of cobalt-doped V3Si alloys, revealing how cobalt doping affects lattice parameters, critical fields, and transition temperatures, and demonstrating type-II superconductivity in these materials.

Contribution

It reports the superconducting behavior of V3-xCoxSi alloys, a previously unstudied system, and details how cobalt doping influences their structural and superconducting properties.

Findings

Lattice parameter decreases with cobalt doping.

Superconducting transition temperature varies with cobalt content.

Type-II superconductivity confirmed in all samples.

Abstract

The A15 structure of superconductors is a prototypical type-II superconductor that has generated considerable interest since the early history of superconducting materials. This paper discusses the superconducting properties of previously unreported V3-xCoxSi alloys. It is found that the lattice parameter decreases with increasing cobalt-doped content and leads to an increased residual resistivity ratio (RRR) value of the V3-xCoxSi system. Meanwhile, the superconducting transition temperature (Tc) cobalt-doped content. Furthermore, the fitted data show that the increase of cobalt-doped content also reduces the lower/upper critical fields of the V3-xCoxSi system. Type-II superconductivity is demonstrated on all V3-xCoxSi samples. With higher Co-doped content, V3-xCoxSi alloys may have superconducting and structural phase transitions at low-temperature regions. As the electron/atom (e/a) ratio increases, the Tc variation trend of V3Si is as pronounced as in crystalline alloys and monotonically follows the trend observed for amorphous superconductors.