Temperature Dependence of the Lower Critical Field of the Noncentrosymmetric Superconductor α‐BiPd

Abstract

Temperature variation of the lower critical field in the noncentrosymmetric superconductor α‐BiPd is probed by local magnetization measurements using Hall micromagnetometry, performed down to 0.3 K in a magnetic field applied along the crystallographic b axis. Below a critical temperature 3.8 K, a conventional dependence is found, typical for a single‐band s‐wave superconductor. The obtained data imply an absence of spin‐triplet component in the superconducting wavefunction and marginal multiband effects in this material, which contradicts some literature reports.