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arXiv · 1608.05977

Lattice spin models for non-Abelian Chiral Spin Liquids

P. Lecheminant·A. M. Tsvelik
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Abstract

We suggest a class of two-dimensional lattice spin Hamiltonians describing non-Abelian SU(2) chiral spin liquids - spin-analogues of fractional non-Abelian quantum Hall states- with gapped bulk and gapless chiral edge excitations described by the SU(2)$_n$ Wess-Zumino-Novikov-Witten conformal field theory. The models are constructed from an array of a generalized spin-$n/2$ ladders with multi-spin exchange interaction which are coupled by isolated spins. Such models allow a controllable analytic treatment starting from the one-dimensional limit and are characterized by a bulk gap and non-Abelian SU(2)$_n$ gapless edge excitations.

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P. Lecheminant, A. M. Tsvelik. 2017-04-15. Lattice spin models for non-Abelian Chiral Spin Liquids. https://doi.org/10.1103/physrevb.95.140406

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