Thermal Dephasing in the Laughlin Quasiparticle Interferometer: Chiral Luttinger Liquid Behavior

TL;DR

This paper experimentally investigates the temperature dependence of Aharonov-Bohm oscillation amplitudes in a Laughlin quasiparticle interferometer, confirming chiral Luttinger liquid behavior and identifying deviations at very low temperatures.

Contribution

It provides the first experimental confirmation of thermal dephasing predictions for a g=1/3 chiral Luttinger liquid interferometer, highlighting differences from single-particle systems.

Findings

Oscillation amplitude fits chiral Luttinger liquid theory

Deviations below 20 mK suggest unknown decoherence sources

Results distinguish fractional quantum Hall edge states from single-particle effects

Abstract

We report experimental temperature dependence of the amplitude of Aharonov-Bohm oscillations in the Laughlin quasiparticle interferometer. The results fit very well the thermal dephasing dependence predicted for a g = 1/3 chiral Luttinger liquid interferometer, and are clearly distinct from the activated behavior observed in single-particle resonant tunneling and Coulomb blockade devices. The small deviation from the zero-bias theory seen below 20 mK indicates yet unrecognized source of experimental decoherence, not included in theory.