Visibility recovery by strong interaction in an electronic Mach-Zehnder interferometer

Abstract

We study the evolution of a single-electron packet of Lorentzian shape along an edge of the integer quantum Hall regime or in a Mach-Zehnder interferometer, considering a capacitive Coulomb interaction and using a bosonization approach. When the packet propagates along a chiral quantum Hall edge, we find that its electron density profile becomes more distorted from Lorentzian due to the generation of electron-hole excitations, as the interaction strength increases yet stays in a weak-interaction regime. However, as the interaction strength becomes larger and enters a strong-interaction regime, the distortion becomes weaker and eventually the Lorentzian packet shape is recovered. The recovery of the packet shape leads to an interesting feature of the interference visibility of the symmetric Mach-Zehnder interferometer whose two arms have the same interaction strength. As the interaction strength increases, the visibility decreases from the maximum value in the weak-interaction regime and then increases to the maximum value in the strong-interaction regime. We argue that this counterintuitive result also occurs under other types of interactions.

Fractional Mutual Statistics on Integer Quantum Hall Edges

“…( 1), on each edge. The teleportation of the N = 1 case (without the fractionalization) has been proposed [36] and experimentally supported [31].…”

Fractionalization and anyonic statistics in the integer quantum Hall collider

“…[49]. The second aspect is the restoration of phase coherence [50,51] at low energy when a single chiral channel is present, or N = 0. In bosonization, the boson fields describe the phase of the fermions.…”

“…The restored phase coherence is a result of a Fermi liquid mechanism [54,55] as the phase space available for particle-hole excitation vanishes at low energy. The resulting phase coherence in the electron transfer across the island, also coined as electron teleportation [51,56], has been successfully measured [57,58] by embedding the island and edge channel within a Mach-Zender interferometer. We emphasize that the phase coherence is also responsible for a quantized resistance in the quantum RC circuit [59].…”