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arXiv · 1406.6364

Double-semion topological order from exactly solvable quantum dimer models

Yang Qi·Zheng-Cheng Gu·Hong Yao
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Abstract

We construct a generalized quantum dimer model on two-dimensional nonbipartite lattices including the triangular lattice, the star lattice and the kagome lattice. At the Rokhsar-Kivelson (RK) point, we obtain its exact ground states that are shown to be a fully gapped quantum spin liquid with the double-semion topological order. The ground-state wave function of such a model at the RK point is a superposition of dimer configurations with a nonlocal sign structure determined by counting the number of loops in the transition graph. We explicitly demonstrate the double-semion topological order in the ground states by showing the semionic statistics of monomer excitations. We also discuss possible implications of such double-semion resonating valence bond states to candidate quantum spin-liquid systems discovered experimentally and numerically in the past few years.

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Yang Qi, Zheng-Cheng Gu, Hong Yao. 2015-10-08. Double-semion topological order from exactly solvable quantum dimer models. https://doi.org/10.1103/physrevb.92.155105

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