Deconfinement and criticality in extended two-dimensional dimer models

Anders W. Sandvik

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arXiv · cond-mat/0312097

Deconfinement and criticality in extended two-dimensional dimer models

Anders W. Sandvik

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Abstract

A square-lattice hard-core dimer model with links extending beyond nearest-neighbors is studied using a directed-loop Monte Carlo method. An arbitrarily small fraction of next-nearest-neighbor dimers is found to cause deconfinement, whereas a critical state with $r^{-2}$ distance dependence of the dimer-dimer correlations persists in the presence of longer dimers preserving the bipartite graph structure. However, the critical confinement exponent governing the correlation of two test monomers is non-universal. Implications for resonating-valence-bond states are discussed.

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Anders W. Sandvik. 2005-07-12. Deconfinement and criticality in extended two-dimensional dimer models. https://arxiv.org/abs/cond-mat/0312097

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