Superconducting and Critical Current Properties of NiBi3 Thin Films on Carbon Microfibers and Sapphire

TL;DR

This study investigates the superconducting and critical current properties of NiBi3 thin films on carbon microfibers and sapphire, revealing slightly higher transition temperatures and analyzing critical current densities.

Contribution

It reports the fabrication and characterization of NiBi3 thin films on different substrates, highlighting their superconducting properties and critical current behavior.

Findings

Transition temperatures of 4.3 K and 4.4 K for fibers and films

Critical current density follows Ginzburg-Landau power-law

NiBi3 films show higher Tc than bulk polycrystalline NiBi3

Abstract

The superconducting and critical current properties of thin films of NiBi3 formed on the surface of carbon microfibers and sapphire substrates are reported. The NiBi3 coated carbon microfibers were prepared by reacting 7 {\mu}m diameter Ni-coated (~ 80 nm) carbon fibers with Bi vapor, and thin films on sapphire were formed by exposing electron-beam deposited Ni films (~ 40 - 120 nm) to Bi vapor. The microfibers and films show Tc = 4.3 K and 4.4 K,respectively, which were slightly higher than that reported for bulk polycrystalline NiBi3. The critical current density (Jc) was measured below the transition temperature and is well described by the Ginzburg-Landau power-law.