Protocol for detecting the nonlocality of the multi-Majorana Systems

TL;DR

This paper proposes an experimentally feasible protocol using parity measurements to detect the nonlocality of multi-Majorana systems, distinguishing true Majorana zero modes from trivial states despite environmental noise.

Contribution

It introduces a novel entanglement witness protocol based solely on parity measurements for identifying Majorana nonlocality in multi-Majorana systems.

Findings

Detection probability of ~18% in a 6-site system

Robustness under environmental noise demonstrated

Reduced detection rate with quasiparticle contamination

Abstract

Majorana zero modes (MZMs) are non-Abelian quasiparticles with the potential to serve as topological qubits for fault-tolerant quantum computing due to their ability to encode quantum information nonlocally. In multi-Majorana systems configured into two separated subsystems, nontrivial quantum correlations persist, but the presence of trivial Andreev bound states (ABSs) can obscure this nonlocality if MZM preparation fails. To address this, we propose a protocol using an entanglement witness based solely on parity measurements to distinguish the nonlocal characteristics of MZM systems. Our framework, which is experimentally implementable, achieves a detection probability of approximately 18% in a 6-site system and demonstrates robustness under environmental noise, albeit with a reduced detection rate in the resence of quasiparticle contamination.