Environmental induced renormalization effects in quantum Hall edge states

TL;DR

This paper introduces a general mechanism explaining how environmental factors like noise and dissipation can renormalize tunneling exponents in quantum Hall edge states, impacting experimental observations and the relevance of excitations.

Contribution

It presents a novel theoretical framework for environmental-induced renormalization effects in quantum Hall edge states, applicable to both Abelian and non-Abelian cases, including counter-propagating modes.

Findings

Environmental noise and dissipation significantly alter tunneling exponents.

The mechanism explains strong renormalizations observed experimentally at low temperatures.

Implications for the relevance of excitations in the 5/2 state are discussed.

Abstract

We propose a general mechanism for renormalization of the tunneling exponents in edge states of the fractional quantum Hall effect. Mutual effects of the coupling with out-of-equilibrium 1/f noise and dissipation are considered both for the Laughlin sequence and for composite co- and counter-propagating edge states with Abelian or non-Abelian statistics. For states with counter-propagating modes we demonstrate the robustness of the proposed mechanism in the so called disorder-dominated phase. Prototypes of these states, such as \nu=2/3 and \nu=5/2, are discussed in detail and the rich phenomenology induced by the presence of a noisy environment is presented. The proposed mechanism justifies the strong renormalizations reported in many experimental observations carried out at low temperatures. We show how environmental effects could affect the relevance of the tunneling excitations, leading to important implications in particular for the \nu=5/2 case.