Fingerprints of Majorana bound states in quantum-rings

TL;DR

This paper explores how Majorana bound states influence the spectrum and persistent current in a quantum-ring coupled to a topological superconductor, providing measurable signatures of MBSs.

Contribution

It introduces a Green's function approach to analyze the effects of MBSs on quantum-ring properties, revealing new spectral and current behaviors.

Findings

MBSs induce particle-hole symmetry in the spectrum

Significant reduction of persistent current at strong coupling

Behavior depends on the ring parity

Abstract

In this work, we investigate a quantum-ring coupled to a topological superconductor, hosting Majorana bound states (MBSs). We study the MBSs effects over the spectrum and persistent current along the quantum-ring. To obtain physical quantities, we employ the Green's function formalism. We found that the presence of MBSs leads to dramatic changes in the quantum-ring spectrum by inducing particle-hole symmetry. On the other hand, we have obtained a substantial reduction of the persistent current in the strong coupling limit between ring and MBSs depending on the ring parity. These behaviors provide a measurable signature of MBSs. Our findings could be used as additional information on MBSs presence in these quantum systems.