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arXiv · 1303.6963

Gapped and gapless spin liquid phases on the Kagome lattice from chiral three-spin interactions

Bela Bauer·Brendan P. Keller·Michele Dolfi·Simon Trebst·Andreas W. W. Ludwig
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Abstract

We argue that a relatively simple model containing only SU(2)-invariant chiral three-spin interactions on a Kagome lattice of S=1/2 spins can give rise to both a gapped and a gapless quantum spin liquid. Our arguments are rooted in a formulation in terms of network models of edge states and are backed up by a careful numerical analysis. For a uniform choice of chirality on the lattice, we realize the Kalmeyer-Laughlin state, i.e. a gapped spin liquid which is identified as the nu=1/2 bosonic Laughlin state. For staggered chiralities, a gapless spin liquid emerges which exhibits gapless spin excitations along lines in momentum space, a feature that we probe by studying quasi-two-dimensional systems of finite width. We thus provide a single, appealingly simple spin model (i) for what is probably the simplest realization of the Kalmeyer-Laughlin state to date, as well as (ii) for a non-Fermi liquid state with lines of gapless SU(2) spin excitations.

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Bela Bauer, Brendan P. Keller, Michele Dolfi, Simon Trebst, Andreas W. W. Ludwig. 2014-09-07. Gapped and gapless spin liquid phases on the Kagome lattice from chiral three-spin interactions. https://arxiv.org/abs/1303.6963

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