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arXiv · 2102.08721

Correlated composite approach to fractional quantum Hall effect via edge current

Abstract

The fractional quantum Hall effect (FQHE) is extensively studied, but the explanation for Hall plateau widths and excitation energy gaps remains elusive. We study the effective theory of FQHE built upon experimental inputs of Hall current distribution, edge dynamics, and many-body correlations. We argue that correlated composites of integer spin, comprising electrons and their images, localized at the edge of the incompressible strip are the basic transport entity. We show in the lowest Landau level that Zeeman interactions of these composites produce all odd denominator plateaus and effective fractional charges. Utilizing field-dependent chemical potential and effective g-factor, we fully explain the observed Hall resistivity curve and excitation energy gaps of the half-filling family. The plateau heights are systematically generated by multi-particle correlations, whereas the plateau widths and excitation energy gaps are determined by the correlation strengths. We explicitly show that the Drude-like behavior at half-filling follows from equal strength of multi-particle correlations.

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Jongbae Hong, Soo-Jong Rey. 2021-02-17. Correlated composite approach to fractional quantum Hall effect via edge current. https://arxiv.org/abs/2102.08721

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