Interface currents and magnetization in singlet-triplet superconducting heterostructures: Role of chiral and helical domains

TL;DR

This paper theoretically investigates how chiral and helical domain walls in topological spin-triplet superconductors influence magnetic and transport properties in singlet-triplet heterostructures, revealing controllable spin and charge effects.

Contribution

It introduces a theoretical framework for understanding how domain walls affect magnetization and currents in singlet-triplet heterostructures, highlighting their potential for spintronic applications.

Findings

Domain walls influence the orientation of interface moments and currents.

Phase difference controls static magnetization and edge currents.

Domain walls contribute to spin and charge transport phenomena.

Abstract

Chiral and helical domain walls are generic defects of topological spin-triplet superconductors. We study theoretically the magnetic and transport properties of superconducting singlet-triplet-singlet heterostructure as a function of the phase difference between the singlet leads in the presence of chiral and helical domains inside the spin-triplet region. The local inversion symmetry breaking at the singlet-triplet interface allows the emergence of a static phase-controlled magnetization, and generally yields both spin and charge currents flowing along the edges. The parity of the domain wall number affects the relative orientation of the interface moments and currents, while in some cases the domain walls themselves contribute to spin and charge transport. We demonstrate that singlet-triplet heterostructures are a generic prototype to generate and control non-dissipative spin and charge effects, putting them in a broader class of systems exhibiting spin-Hall, anomalous Hall effects and similar phenomena. Features of the electron transport and magnetic effects at the interfaces can be employed to assess the presence of domains in chiral/helical superconductors.