Controllable creation of topological boundary states in topological-insulator-based Josephson corner junctions

TL;DR

This paper demonstrates the controllable creation of topological boundary states in TI-based Josephson junctions, which could serve as a platform for Majorana zero modes and topological quantum computing.

Contribution

It reports the experimental realization of a controllable topological boundary state in Josephson junctions based on topological insulators, advancing the understanding of MZMs in TQC.

Findings

Topological boundary states are controllably created at junction corners.

The states exhibit a 4π-period energy-phase relation.

Potential platform for hosting and braiding MZMs.

Abstract

Majorana zero modes (MZMs) in condensed matter systems have attracted great attention in the past two decades, due to their interesting physics and potential application in topological quantum computing (TQC). However, the topologically protected nature of MZMs still need more experimental verifications. In this study, we have realized controllable creation of a topological boundary state at the corner of topological insulator (TI)-based Josephson corner junctions. This state demonstrates protected existence across a broad region in parametric space, and exhibits a non-2{\pi}-period but 4{\pi}-period-compatible energy-phase relation. Our study suggests that TI-based Josephson junctions, as proposed in the Fu-Kane scheme of TQC, may provide a promising platform for hosting and braiding MZMs.