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arXiv · 1101.2111

Extended Quantum Dimer Model and novel valence-bond phases

Kouki Nakata·Keisuke Totsuka
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Abstract

We extend the quantum dimer model (QDM) introduced by Rokhsar and Kivelson so as to construct a concrete example of the model which exhibits the first-order phase transition between different valence-bond solids suggested recently by Batista and Trugman and look for the possibility of other exotic dimer states. We show that our model contains three exotic valence-bond phases (herringbone, checkerboard and dimer smectic) in the ground-state phase diagram and that it realizes the phase transition from the staggered valence-bond solid to the herringbone one. The checkerboard phase has four-fold rotational symmetry, while the dimer smectic, in the absence of quantum fluctuations, has massive degeneracy originating from partial ordering only in one of the two spatial directions. A resonance process involving three dimers resolves this massive degeneracy and dimer smectic gets ordered (order from disorder).

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Kouki Nakata, Keisuke Totsuka. 2011-01-11. Extended Quantum Dimer Model and novel valence-bond phases. https://doi.org/10.1088/1742-5468%2F2011%2F01%2Fp01033

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