Spin-triplet pairing and spin supercurrent in -wave magnetic superconductors
Phys. Rev. B 113, 214511 – Published 5 June, 2026
DOI: https://doi.org/10.1103/byxq-7xdc
Abstract
Spin-triplet superconductors are promising platforms for dissipationless spin transport, which typically originates from the interplay of ferromagnetism and superconductivity. However, ferromagnetism, in turn, suppresses superconductivity. As a class of unconventional magnetic materials, -wave magnets possess the advantage of odd-parity spin splitting without net magnetism. Here we demonstrate through site-resolved spin-polarized band analysis that -wave magnets exhibit nonzero in-plane spin polarization, which is crucial for spin-triplet correlations. We then investigate the -wave magnetic superconductor composed of a -wave -wave superconductor hybrid system and calculate the site-resolved equal-spin component of anomalous Green's function, revealing the existence of equal-spin (spin-triplet) Cooper pairs. Next, we construct a normal -wave magnetic superconductor junction and calculate the equal-spin Andreev reflection coefficient using the nonequilibrium Green's function method. The results show that the equal-spin Andreev reflection coefficient is indeed nonzero, owing to the spin-triplet superconductivity. Finally, we construct a Josephson junction based on -wave magnetic superconductors, study the spin Josephson effect, and identify the emergence of a spin superconducting diode effect.