Endstates in multichannel spinless p-wave superconducting wires

TL;DR

This paper investigates how different terminations of multichannel spinless p-wave superconducting wires affect the energies of localized endstates, revealing that termination type significantly influences subgap state energies.

Contribution

It provides a comparative analysis of endstate energies in superconducting wires with various terminations, highlighting the impact of boundary conditions on subgap states.

Findings

Endstate energies vary with wire termination type.

Smooth confinement can alter subgap state energies.

Disorder and normal-metal coupling influence endstate energies.

Abstract

Multimode spinless p-wave superconducting wires with a width W much smaller than the superconducting coherence length \xi are known to have multiple low-energy subgap states localized near the wire's ends. Here we compare the typical energies of such endstates for various terminations of the wire: A superconducting wire coupled to a normal-metal stub, a weakly disordered superconductor wire and a wire with smooth confinement. Depending on the termination, we find that the energies of the subgap states can be higher or lower than for the case of a rectangular wire with hard-wall boundaries.