Enhanced $2\pi$-periodic Aharonov-Bohm Effect as a Signature of Majorana Zero Modes Probed by Nonlocal Measurements

TL;DR

This paper introduces a $2 ext{-}m{ extpi}$-periodic Aharonov-Bohm effect as a nonlocal method to detect Majorana zero modes, highlighting its robustness and ability to distinguish topological states from trivial bound states.

Contribution

It proposes a novel nonlocal measurement technique based on the $2 ext{-}m{ extpi}$-periodic AB effect to identify Majorana zero modes without fermion parity restrictions.

Findings

Enhanced AB effect due to topological protection of MZMs

Nonlocal index distinguishes trivial from topological bound states

Robustness of the effect against trivial bound state interference

Abstract

We propose the $2\pi$-periodic Aharonov-Bohm (AB) effect as a nonlocal probe of Majorana zero modes (MZMs) without the restriction of fermion parity. We demonstrate the enhancement of the AB effect, where the topological protection of MZMs yields amplified and robust Andreev reflection mediated by MZMs at multiple superconductor-normal metal junctions. We investigate the influence of trivial bound states and show that a nonlocal index enables a more explicit distinction between the trivial and topological bound states than local probes.