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arXiv · 2207.11921

Energy Gaps and Plateau Characteristics in the Fractional Quantum Hall Effect Derive from Multi-particle Correlations

Abstract

The energy gaps appearing in the fractional quantum Hall effect (FQHE) remain an essential aspect of the investigation. Moreover, the plateau widths in the Hall resistance have been considered simply an effect of disorder as in the integral quantum Hall effect. The existing theories could neither explain the Hall resistance curve owing to plateau widths nor calculate the energy gaps. This study reveals that both the energy gaps and plateau widths contain fundamental many-body aspects of the FQHE. They are found to be connected via the strengths of multi-particle correlations, which do not affect the plateau heights. They are automatically quantized just by the presence of multi-particle correlations. This work focuses on correlated skipping electrons moving through the edge of an incompressible strip formed within a Hall bar. Consequently, a single-particle Hamiltonian was constructed incorporating the Zeeman energies of multiply-correlated skipping electrons. The resulting energy spectrum exhibits hierarchical splits of the Landau levels according to correlation order. The lowest Landau level is examined. Based on such level splitting, a previously measured Hall resistance curve and energy gaps are quantitatively explained by determining the parameters that describe the degrees of multi-particle correlations. The chemical potential and effective $g$-factors are additionally predicted for the Hall resistance. Furthermore, the fractional electron charge $e/(2n+1)$ for an electron participating in $n$-particle correlation was obtained by identifying the Fermi distribution function of $n$ correlated basic transport entities moving through the edge of the incompressible strip. Finally, the ideal-like Hall resistance was obtained at half-filling using the strengths of multi-particle correlations given in a regular pattern.

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BibTeXRIS

Jongbae Hong. 2022-07-25. Energy Gaps and Plateau Characteristics in the Fractional Quantum Hall Effect Derive from Multi-particle Correlations. https://arxiv.org/abs/2207.11921

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