Tunneling Conductance in Superconducting Junctions with p-wave Unconventional Magnets Breaking Time-reversal Symmetry

Abstract A new type of magnet called p -wave unconventional magnet is proposed, stimulated by the discovery of altermagnet. We study the tunneling conductance of p -wave unconventional magnet/superconductor junctions by adopting the effective Hamiltonian of p -wave unconventional magnets with time-reversal symmetry breaking, suggested (Hellenes et al. P-wave magnets, http://arxiv.org/abs/2309.01607 2024). The tunneling conductance shows an asymmetric behavior with respect to bias voltage in the helical p -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 p -wave unconventional magnets. In chiral d and p -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 (Maeda et al. J. Phys. Soc. Jpn. 93 , 114703 2024), where only the odd function of the exchange coupling of p -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.