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arXiv · 2007.08870

Abelian topological order of $ν=2/5$ and $3/7$ fractional quantum Hall states in lattice models

Bartholomew Andrews·Madhav Mohan·Titus Neupert
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Abstract

Determining the statistics of elementary excitations supported by fractional quantum Hall states is crucial to understanding their properties and potential applications. In this paper, we use the topological entanglement entropy as an indicator of Abelian statistics to investigate the single-component $ν=2/5$ and $3/7$ states for the Hofstadter model in the band mixing regime. We perform many-body simulations using the infinite cylinder density matrix renormalization group and present an efficient algorithm to construct the area law of entanglement, which accounts for both numerical and statistical errors. Using this algorithm, we show that the $ν=2/5$ and $3/7$ states exhibit Abelian topological order in the case of two-body nearest-neighbor interactions. Moreover, we discuss the sensitivity of the proposed method and fractional quantum Hall states with respect to interaction range and strength.

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Bartholomew Andrews, Madhav Mohan, Titus Neupert. 2021-02-18. Abelian topological order of $ν=2/5$ and $3/7$ fractional quantum Hall states in lattice models. https://doi.org/10.1103/physrevb.103.075132

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