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arXiv · 1204.1697

Fractional Quantum Hall Effect in Topological Flat Bands with Chern Number Two

Yi-Fei Wang·Hong Yao·Chang-De Gong·D. N. Sheng
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Abstract

Recent theoretical works have demonstrated various robust Abelian and non-Abelian fractional topological phases in lattice models with topological flat bands carrying Chern number C=1. Here we study hard-core bosons and interacting fermions in a three-band triangular-lattice model with the lowest topological flat band of Chern number C=2. We find convincing numerical evidence of bosonic fractional quantum Hall effect at the $ν=1/3$ filling characterized by three-fold quasi-degeneracy of ground states on a torus, a fractional Chern number for each ground state, a robust spectrum gap, and a gap in quasihole excitation spectrum. We also observe numerical evidence of a robust fermionic fractional quantum Hall effect for spinless fermions at the $ν=1/5$ filling with short-range interactions.

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Yi-Fei Wang, Hong Yao, Chang-De Gong, D. N. Sheng. 2012-10-26. Fractional Quantum Hall Effect in Topological Flat Bands with Chern Number Two. https://doi.org/10.1103/physrevb.86.201101

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