Quantum Hall interferometry at finite bias with multiple edge channels

Electronic interferometry has emerged as a powerful tool to extract information about 2D electron liquids, including fractional statistics of anyons in the quantum Hall effect. The existing theory mostly addresses the conceptually simplest case of a single edge mode, but recent experiments have focused on multichannel edges. Motivated by recent experiments, the authors consider here a quantum Hall interferometer model containing two edge modes and study theoretically the current-voltage curves for various values of the relative edge velocities, interaction strength, and the temperature. When the inner mode is completely reflected and the outer mode is partially transmitted, the authors find striking features related to resonance of excitations of the closed inner channel. Fluctuations in the charge of the closed inner mode, caused by sparse tunneling events, lead to an exponential suppression of the interference visibility at high voltages, in agreement with experiments.