Skyrmion-induced subgap states in p-wave superconductors

TL;DR

This paper investigates how skyrmions in p-wave superconductors create unique bound states within the spectral gap, offering potential new experimental methods to probe p-wave superconductivity.

Contribution

It demonstrates that skyrmions induce isolated subgap bound states in p-wave superconductors, contrasting with s-wave cases, and provides a theoretical framework for their detection.

Findings

Skyrmions induce subgap bound states in p-wave superconductors.

The bound states are spectrally isolated from other states.

Predicted features can be observed via scanning tunneling microscopy.

Abstract

In s-wave systems, it has been theoretically shown that a ferromagnetic film hosting a skyrmion can induce a bound state embedded in the opposite-spin continuum. In this work, we consider a case of skyrmion-induced state in a p-wave superconductor. We find that the skyrmion induces a bound state that generally resides \emph{within} the spectral gap and is isolated from all other states, in contrast to the case of conventional superconductors. To this end, we derive an approximate expression for the $T$-matrix, through which we calculate the spin-polarized local density of states which is observable in scanning tunneling microscopy measurements. We find the unique spectroscopic features of the skyrmion-induced bound state and discuss how our predictions could be employed as novel experimental probes for p-wave superconducting states.