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arXiv:1509.03070 · Physical Review Letters

Kagome Chiral Spin Liquid as a Gauged U ( 1 ) Symmetry Protected Topological Phase

Yin-Chen He, Subhro Bhattacharjee, Frank Pollmann, Roderich Moessner

Published Dec 30, 2015• 31 citations
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Abstract

While the existence of a chiral spin liquid (CSL) on a class of spin-1/2 kagome antiferromagnets is by now well established numerically, a controlled theoretical path from the lattice model leading to a low-energy topological field theory is still lacking. This we provide via an explicit construction starting from reformulating a microscopic model for a CSL as a lattice gauge theory and deriving the low-energy form of its continuum limit. A crucial ingredient is the realization that the bosonic spinons of the gauge theory exhibit a U(1) symmetry protected topological (SPT) phase, which upon promoting its U(1) global symmetry to a local gauge structure ("gauging"), yields the CSL. We suggest that such an explicit lattice-based construction involving gauging of a SPT phase can be applied more generally to understand topological spin liquids.

DOI
10.1103/physrevlett.115.267209

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Kagome spin liquid: a deconfined critical phase driven by U(1)U(1)U(1) gauge fluctuation
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