Yi-Fei Wang, Hong Yao, Chang-De Gong, D. N. Sheng
Recent theoretical works have demonstrated various robust Abelian and non-Abelian fractional quantum Hall states in lattice models with topological flat bands carrying a Chern number C=1. Here we study hard-core bosons 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 $\nu=1/3$ filling characterized by three-fold quasi-degeneracy of ground states on a torus, a fractional quantized Chern number for each ground state, a robust spectrum gap, and a gap in quasihole excitation spectrum. More surprisingly for the 1/4 filling, fractional quantum Hall features are also observed, while the topological ground-state degeneracy varies with the particle numbers and shows a strong even-odd effect.
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http://arxiv.org/abs/1204.1697
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