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arXiv · 2308.10190

Two-fluid theory of composite bosons and fermions and the quantum Hall proximity effect

Zhaoyu Han·Kyung-Su Kim·Steven A. Kivelson·Thors Hans Hansson
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Abstract

We propose a two-fluid description of fractional quantum Hall systems, in which one component is a condensate of composite bosons and the other a Fermi liquid formed by composite fermions (or simply electrons). We employ the theory to model the interface between a fractional quantum Hall liquid and a (composite) Fermi liquid metal, where we find a penetration of quantum Hall condensate into the metallic region reminiscent of the proximity effect in superconductor-metal interfaces. We also find a novel and physically reasonable set of gapped quasielectron and neutral modes in fractional quantum Hall liquids.

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Zhaoyu Han, Kyung-Su Kim, Steven A. Kivelson, Thors Hans Hansson. 2023-08-20. Two-fluid theory of composite bosons and fermions and the quantum Hall proximity effect. https://doi.org/10.1103/physrevb.108.195117

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