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arXiv · 1702.03794

Clustering of Topological Charges in a Kagome Classical Spin Liquid

Tomonari Mizoguchi·Ludovic D. C. Jaubert·Masafumi Udagawa
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Abstract

Fractionalization is a ubiquitous phenomenon in topological states of matter. In this work, we study the collective behavior of fractionalized topological charges and their instabilities, through the $J_1$-$J_2$-$J_3$ Ising model on a kagome lattice, which can be mapped to a model of interacting topological charges under the constraint of Gauss' law. We find that the recombination of topological charges gives rise to a yet unexplored classical spin liquid. This spin liquid is characterized by an extensive residual entropy, as well as the formation of hexamers of same-sign topological charges. The emergence of hexamers is reflected to a half-moon signal in the magnetic structure factor, which provides us a signature of this new spin liquid in neutron-scattering experiments. To study this phase, a worm algorithm has been developed which does not require the usual divergence-free condition.

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Tomonari Mizoguchi, Ludovic D. C. Jaubert, Masafumi Udagawa. 2017-08-22. Clustering of Topological Charges in a Kagome Classical Spin Liquid. https://doi.org/10.1103/physrevlett.119.077207

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