paper

Tunneling conductance in superconducting junctions with -wave unconventional magnets breaking time-reversal symmetry

arXiv:2506.13372 · doi:10.1007/s10948-025-07064-w

Abstract

A new type of magnet called -wave unconventional magnet is proposed, stimulated by the discovery of altermagnet. We study the tunneling conductance of -wave unconventional magnet/superconductor junctions by adopting the effective Hamiltonian of -wave unconventional magnets with time-reversal symmetry breaking, suggested in Ref [arXiv: 2309.01607 (2024)]. The tunneling conductance shows an asymmetric behavior with respect to bias voltage in the helical -wave superconductor junctions. It is caused by the missing of helical edge states contributing to the charge conductance owing to the momentum-dependent spin-split feature of the Fermi surface in -wave unconventional magnets. In chiral and -wave superconductor junctions, the resulting spin-resolved tunneling conductance takes a different value for spin sectors due to the time-reversal symmetry breaking in superconductors. Our results qualitatively reproduce the results based on the simplified Hamiltonian in Ref [J.\ Phys.\ Soc.\ Jpn.\ \textbf{93}, 114703 (2024)], where only the odd function of the exchange coupling of -wave unconventional magnets is taken into account, which gives the shift of the Fermi surface and preserves the time-reversal symmetry similar to the spin-orbit coupling.

15 pages, 10 figures

References in corpus (81)

Cited by in corpus (3)