Edge currents as a probe of the strongly spin-polarized topological noncentrosymmetric superconductors

TL;DR

This paper explores how antisymmetric spin-orbit coupling influences the topological and transport properties of noncentrosymmetric superconductors, revealing edge currents as a probe of their spin polarization and chiral symmetry breaking.

Contribution

It analyzes the effects of Rashba and Dresselhaus spin-orbit couplings on topological edge modes and transport in noncentrosymmetric superconductors, highlighting the role of broken chiral symmetry.

Findings

Spin-orbit coupling modifies topological edge states.

Broken chiral symmetry induces uni-directional edge currents.

Edge response to exchange fields reveals spin polarization.

Abstract

Recently the influence of antisymmetric spin-orbit coupling has been studied in novel topological superconductors such as half-Heuslers and artificial hetero-structures. We investigate the effect of Rashba and/or Dresselhaus spin-orbit couplings on the band structure and topological properties of a two-dimensional noncentrosymetric superconductor. For this goal, the topological helical edge modes are analyzed for different spin-orbit couplings as well as for several superconducting pairing symmetries. To explore the transport properties, we examine the response of the spin-polarized edge states to an exchange field in a superconductor-ferromagnet heterostructure. The broken chiral symmetry causes the uni-directional currents at opposite edges.