Theory of Tunneling Spectroscopy in Unconventional $p$-wave Magnet-Superconductor Hybrid Structures

TL;DR

This paper provides a theoretical analysis of tunneling conductance in a hybrid structure combining an unconventional p-wave magnet and a superconductor, revealing how surface states influence conductance features across different pairing symmetries.

Contribution

It introduces a theoretical framework for tunneling spectroscopy in magnet-superconductor hybrids, highlighting the effects of surface Andreev bound states on conductance signatures for various pairing symmetries.

Findings

Zero bias conductance peaks are insensitive to magnetic spin-splitting in certain symmetries.

Dispersive surface states cause non-monotonic conductance changes with magnetic field.

Results aid in identifying pairing symmetries of unconventional superconductors.

Abstract

We theoretically study the tunneling conductance of a junction consisting of a two-dimensional unconventional $p$-wave magnet (UPM) and a superconductor (SC) for various pairing symmetries. The zero bias conductance peaks arising from the dispersionless surface Andreev bound states (SABSs) in $d_{xy}$-wave and $p_{x}$-wave superconductor junctions are insensitive against varying the magnetic spin-splitting strength $\alpha _{y}$. Moreover, for chiral $p$- or chiral $d$-wave SCs, zero bias conductance shows a non-monotonic change as a function of $\alpha_{y}$ indicating the existence of the dispersive SABSs. Our obtained results of tunneling spectroscopy based on a UPM serve as an effective way for the identification of the pairing symmetries of unconventional superconductors. It is noted that our used Hamiltonian of UPM is also available for persistent spin helix systems.