Magnetic chains on a triplet superconductor

TL;DR

This paper explores how magnetic impurities on a triplet superconductor can alter its topological states, leading to zero modes and chiral edge modes, with implications for topological quantum systems.

Contribution

It investigates the effects of magnetic chains and islands on the topological properties of 2D triplet superconductors, revealing conditions for zero modes and chiral edge states.

Findings

Magnetic chains can eliminate edge states and create localized zero modes.

Increasing impurity density induces a finite Chern number and chiral modes.

Small impurity concentrations at half-filling can generate chiral edge modes.

Abstract

The topological state of a two-dimensional triplet superconductor may be changed by an appropriate addition of magnetic impurities. A ferromagnetic magnetic chain at the surface of a superconductor with spin-orbit coupling may eliminate the edge states of a finite system giving rise to localized zero modes at the edges of the chain. The coexistence/competition between the two types of zero modes is considered. The reduction of the system to an effective $1d$ system gives partial information on the topological properties but the study of the two sets of zero modes requires a two-dimensional treatment. Increasing the impurity density from a magnetic chain to magnetic islands leads to a finite Chern number. At half-filling small concentrations are enough to induce chiral modes.