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

Tong Zhou, Matthieu C. Dartiailh, Kasra Sardashti, Jong E. Han, Alex Matos-Abiague, Javad Shabani, Igor Zutic

Published 2021-01-22Version 1

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 (JJ) and demonstrate non-Abelian statistics through MBS fusion, detected by charge sensing using a quantum point contact. The feasibility of preparing, manipulating, and fusing MBS in two-dimensional (2D) systems is supported in our experiments which demonstrate the control of 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.