Fusion of Majorana Bound States with Mini-Gate Control in Two-Dimensional Systems

TL;DR

This paper proposes a method to demonstrate non-Abelian statistics of Majorana bound states in 2D systems using mini-gate controlled Josephson junctions, supported by simulations and experiments on InAs/Al devices.

Contribution

It introduces a new approach to detect non-Abelian statistics through MBS fusion in 2D systems with mini-gate control, combining theoretical simulations and experimental validation.

Findings

Successful gate control of topological transition in InAs/Al JJs

Demonstration of MBS fusion detection via charge sensing

Feasibility of manipulating MBS in 2D systems

Abstract

A hallmark of topological superconductivity is the non-Abelian statistics of Majorana bound states (MBS), its chargeless zero-energy emergent quasiparticles. The resulting fractionalization of a single electron, stored nonlocally as a two spatially-separated MBS, provides a powerful platform for implementing fault-tolerant topological quantum computing. However, despite intensive efforts, experimental support for MBS remains indirect and does not probe their non-Abelian statistics. Here we propose how to overcome this obstacle in mini-gate controlled planar Josephson junctions (JJs) and demonstrate non-Abelian statistics through MBS fusion, detected by charge sensing using a quantum point contact, based on dynamical simulations. The feasibility of preparing, manipulating, and fusing MBS in two-dimensional (2D) systems is supported in our experiments which demonstrate the gate control of topological transition and superconducting properties with five mini gates in InAs/Al-based JJs. While we focus on this well-established platform, where the topological superconductivity was already experimentally detected, our proposal to identify elusive non-Abelian statistics motivates also further MBS studies in other gate-controlled 2D systems.