Quantum Hall line junction with impurities as a multi-slit Luttinger liquid interferometer

TL;DR

This paper demonstrates quantum interference in quantum Hall edge states through resonant tunneling, revealing extended phase coherence and modeling the system as a multi-slit Luttinger liquid interferometer.

Contribution

It introduces a novel interferometer model using quantum Hall edge states with impurities, showing extended phase coherence and resonant tunneling effects.

Findings

Observed Aharonov-Bohm oscillations indicating quantum interference.

Established a lower bound of 20-40 μm for phase coherence length.

Confirmed extended phase coherence of quantum Hall edge states.

Abstract

We report on quantum interference between a pair of counterpropagating quantum Hall edge states that are separated by a high quality tunnel barrier. Observed Aharonov-Bohm oscillations are analyzed in terms of resonant tunneling between coupled Luttinger liquids that creates bound electronic states between pairs of tunnel centers that act like interference slits. We place a lower bound in the range of 20-40 $\mu$m for the phase coherence length and directly confirm the extended phase coherence of quantum Hall edge states.