Exploration of noncentrosymmetric superconductors in the ZrNiAl family via high-throughput <i>ab-initio</i> calculations

Abstract

The search for functional noncentrosymmetric superconductors (NCSs) is a topic of interest in the physics community, as NCSs provide an ideal platform for exploring the fascinating quantum phenomenon originating from the inversion symmetry breaking. In this work, based on first-principles calculations, we conducted a systematic high-throughput crystal structure screening and electronic property study of NCSs with the ZrNiAl structure. Through a series of stability assessments, we screened out 11 candidate materials with superior stability in the ZrNiAl system among 4410 configurations. Moreover, the results of electron–phonon coupling strength calculations indicate that nine compounds are superconducting phases. Furthermore, we identified five superconducting compounds that exhibit significant band splitting near the Fermi surface. We find that AlOsNb and InIrZr exhibit strong Ising spin–orbit coupling characteristics and are predicted to display large in-plane upper critical fields that may significantly exceed the Pauli limit. Among the two, AlOsNb stands out as an exceptional experimental candidate for exploring bulk Ising superconductivity, due to its pronounced Ising band splitting near the Fermi surface.