Two-particle time-domain interferometry in the Fractional Quantum Hall Effect regime

TL;DR

This paper demonstrates that anyons in the Fractional Quantum Hall regime maintain quantum coherence during propagation, using a novel two-particle interferometry approach, which is promising for quantum information applications.

Contribution

It introduces a new interferometric method to show that anyons preserve quantum coherence while propagating, advancing understanding of their potential for quantum computing.

Findings

Achieved 53% and 60% interference visibility for e/5 and e/3 anyons.

Demonstrated quantum coherence of anyons during propagation.

Provided evidence supporting controlled quantum braiding of anyons.

Abstract

Quasi-particles are elementary excitations of condensed matter quantum phases. Demonstrating that they keep quantum coherence while propagating is a fundamental issue for their manipulation for quantum information tasks. Here, we consider anyons, the fractionally charged quasi-particles 20 of the Fractional Quantum Hall Effect occurring in two-dimensional electronic conductors in high magnetic fields. They obey anyonic statistics, intermediate between fermionic and bosonic. Surprisingly, anyons show large quantum coherence when transmitted through the localized states of electronic Fabry-P\'erot interferometers, but almost no quantum interference when transmitted via the propagating states of Mach-Zehnder interferometers. Here, using a novel interferometric 25 approach, we demonstrate that anyons do keep quantum coherence while propagating. Performing two-particle time-domain interference measurements sensitive to the two-particle Hanbury Brown Twiss phase, we find 53% and 60% visibilities for anyons with charges e/5 and e/3. Our results give a positive message for the challenge of performing controlled quantum coherent braiding of anyons.