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arXiv · 1110.4980

Non-Abelian Quantum Hall Effect in Topological Flat Bands

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

Inspired by recent theoretical discovery of robust fractional topological phases without a magnetic field, we search for the non-Abelian quantum Hall effect (NA-QHE) in lattice models with topological flat bands (TFBs). Through extensive numerical studies on the Haldane model with three-body hard-core bosons loaded into a TFB, we find convincing numerical evidence of a stable $ν=1$ bosonic NA-QHE, with the characteristic three-fold quasi-degeneracy of ground states on a torus, a quantized Chern number, and a robust spectrum gap. Moreover, the spectrum for two-quasihole states also shows a finite energy gap, with the number of states in the lower energy sector satisfying the same counting rule as the Moore-Read Pfaffian state.

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Yi-Fei Wang, Hong Yao, Zheng-Cheng Gu, Chang-De Gong, D. N. Sheng. 2012-03-22. Non-Abelian Quantum Hall Effect in Topological Flat Bands. https://doi.org/10.1103/physrevlett.108.126805

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