Fabry-Pérot Interferometry at the ν=2/5 Fractional Quantum Hall State

Electronic Fabry-Pérot interferometry is a powerful method to probe quasiparticle charge and anyonic braiding statistics in the fractional quantum Hall regime. We extend this technique to the hierarchy ν=2/5 fractional quantum Hall state, possessing two edge modes that in our device can be interfered independently. The outer edge mode exhibits interference similar to the behavior observed at the ν=1/3 state, indicating that the outer edge mode at ν=2/5 has properties similar to the single mode at ν=1/3. The inner mode shows an oscillation pattern with a series of discrete phase jumps indicative of distinct anyonic braiding statistics. After taking into account the impact of bulk-edge coupling, we extract an interfering quasiparticle charge e*=0.17±0.02 and anyonic braiding phase θa=(−0.43±0.05)×2π, which serve as experimental verification of the theoretically predicted values of e*=15 and θa=−(4π/5).Received 18 April 2023Revised 1 August 2023Accepted 22 August 2023DOI:https://doi.org/10.1103/PhysRevX.13.041012Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.Published by the American Physical SocietyPhysics Subject Headings (PhySH)Research AreasCoulomb blockadeGeometric & topological phasesQuantum interference effectsCondensed Matter, Materials & Applied PhysicsQuantum Information, Science & Technology