# Neutral modes edge state dynamics through quantum point contacts

## TL;DR

This paper investigates the dynamics of neutral modes in fractional quantum Hall states through a quantum point contact, highlighting the role of neutral modes in tunnelling processes and current fluctuations.

## Contribution

It generalizes the effective field theory for edge states to include propagating neutral modes and analyzes the crossover in backscattering current between different quasiparticle tunnelling regimes.

## Key findings

- Neutral modes are essential for explaining the crossover phenomena.
- Higher order cumulants reveal the competition between different carrier charges.
- The study identifies dominant tunnelling processes in the presence of interactions.

## Abstract

Dynamics of neutral modes for fractional quantum Hall states is investigated for a quantum point contact geometry in the weak-backscattering regime. The effective field theory introduced by Fradkin-Lopez for edge states in the Jain sequence is generalized to the case of propagating neutral modes. The dominant tunnelling processes are identified also in the presence of non-universal phenomena induced by interactions. The crossover regime in the backscattering current between tunnelling of single-quasiparticles and of agglomerates of p-quasiparticles is analysed. We demonstrate that higher order cumulants of the backscattering current fluctuations are a unique resource to study quantitatively the competition between different carrier charges. We find that propagating neutral modes are a necessary ingredient in order to explain this crossover phenomena.