Edge-State Velocity and Coherence in a Quantum Hall Fabry-Perot Interferometer

TL;DR

This study examines nonlinear transport in quantum Hall Fabry-Perot interferometers, revealing how edge-state velocities and coherence are affected by magnetic field and bias, with implications for quantum coherence control.

Contribution

It provides experimental measurements of edge-state velocities and coherence effects, comparing them to models and identifying a crossover in electron dynamics.

Findings

Checkerboard conductance pattern observed

Edge velocities match model predictions across regimes

Dephasing explains visibility suppression

Abstract

We investigate nonlinear transport in electronic Fabry-Perot interferometers in the integer quantum Hall regime. For interferometers sufficiently large that Coulomb blockade effects are absent, a checkerboard-like pattern of conductance oscillations as a function of dc bias and perpendicular magnetic field is observed. Edge-state velocities extracted from the checkerboard data are compared to model calculations and found to be consistent with a crossover from skipping orbits at low fields to E x B drift at high fields. Suppression of visibility as a function of bias and magnetic field is accounted for by including energy- and field-dependent dephasing of edge electrons.