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Can Quasi-Particles Tunnel Through A Barrier?

Elad Shopen·Yuval Gefen·Yigal Meir
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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.

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Elad Shopen, Yuval Gefen, Yigal Meir. 2004-06-20. Can Quasi-Particles Tunnel Through A Barrier?. https://arxiv.org/abs/cond-mat/0406452

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