Can Quasi-Particles Tunnel Through A Barrier?

TL;DR

This paper investigates whether fractionally charged particles in the fractional quantum Hall effect can tunnel through barriers, using a microscopic analysis in a torus geometry and proposing an experimentally testable setup.

Contribution

It provides a systematic microscopic analysis of tunnelling of fractional charges in FQHE and suggests a new experimental configuration to verify the phenomenon.

Findings

Fractional charges can tunnel through barriers in certain geometries.

A microscopic analysis of adiabatic charge pumping was performed.

Proposes an experimentally feasible setup for observing tunnelling.

Abstract

This is a qualitative description of a systematic analysis carried out by us. We address the question of whether fractionally charged particles, in the context of the fractional quantum Hall effect (FQHE) can tunnel through a potential barrier (around which the density of the quantum Hall liquid is practically zero). Setting the barrier in a multiply-connected FQHE geometry removes the "global constraint" which prohibits such tunnelling. We have performed a microscopic analysis of adiabatic charge pumping and tunnelling in a torus geometry. Below we summarize our analysis in semi-qualitative terms. We also propose a setup-- different from the torus geometry-- amenable to experimental verification.