Interaction between domain walls in chiral p-wave superconductors

TL;DR

This paper microscopically calculates the interaction energy between domain walls in chiral p-wave superconductors, revealing how quasiparticles mediate this interaction and providing a general expression for free energy in nonuniform order parameter textures.

Contribution

It introduces a microscopic calculation of domain wall interactions and derives a general free energy expression based on quasiparticle scattering in chiral p-wave superconductors.

Findings

Interaction energy depends on quasiparticle scattering at domain walls

Derived a general free energy expression for nonuniform order parameters

Provides insights into quasiparticle-mediated interactions in superconductors

Abstract

We calculate microscopically the interaction energy of domain walls separating degenerate ground states in a chiral p-wave superconductor. The interaction is mediated by the quasiparticles experiencing Andreev scattering at the domain walls. As a by-product, we derive a useful general expression for the free energy of an arbitrary nonuniform texture of the order parameter in terms of the quasiparticle scattering matrix.