Evolution of superconductivity and corresponding electronic structure in pressurized Nb3Sn

The studies on superconductors under extreme conditions offer valuable insights for assessing their potential in new applications. Nb 3 Sn, an intermetallic alloy with an A15 structure, is a key commercial superconductor known for its high critical current and magnetic field tolerance. Here, we systematically investigated the physical properties of Nb 3 Sn under high pressures. Our findings reveal that superconductivity in Nb 3 Sn remains robust up to ∼ 142 GPa, demonstrating remarkable stability despite a gradual suppression of T c with increasing pressure. First-principles calculations indicate that the pressure-dependent superconducting behavior is primarily driven by variations in the density of states of Nb’s d-electrons, particularly contributions from the d x 2 − y 2 and d z 2 orbitals. Furthermore, we predict the potential for synthesizing Nb 3 Sn films and demonstrate that biaxial strain induced by suitable substrates can preserve their superconducting properties. This comprehensive study not only enhances our understanding of Nb 3 Sn’s superconducting mechanism under high pressure but also opens new avenues for its application in advanced superconducting technologies.