Non-Topological Majorana Zero Modes in Inhomogeneous Spin Ladders

TL;DR

This paper demonstrates that inhomogeneous Heisenberg spin ladders can host zero energy Majorana bound states at interfaces, which, despite lacking topological protection, exhibit notable resilience and potential for practical applications.

Contribution

It introduces a new class of Majorana zero modes in inhomogeneous spin ladders that are non-topological but still resilient, expanding the understanding of Majorana states beyond topological systems.

Findings

Interfacial Majorana states form in coupled spin ladders.

These states are not topologically protected but are resilient.

Potential for practical applications due to robustness.

Abstract

We show that the coupling of homogeneous Heisenberg spin-1/2 ladders in different phases leads to the formation of interfacial zero energy Majorana bound states. Unlike Majorana bound states at the interfaces of topological quantum wires, these states are void of topological protection and generally susceptible to local perturbations of the host spin system. However, a key message of our work is that in practice they show a high degree of resilience over wide parameter ranges which may make them interesting candidates for applications.