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arXiv · 1507.04643

Phase diagram of an extended quantum dimer model on the hexagonal lattice

T. M. Schlittler·T. Barthel·G. Misguich·J. Vidal·R. Mosseri
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Abstract

We introduce a quantum dimer model on the hexagonal lattice that, in addition to the standard three-dimer kinetic and potential terms, includes a competing potential part counting dimer-free hexagons. The zero-temperature phase diagram is studied by means of quantum Monte Carlo simulations, supplemented by variational arguments. It reveals some new crystalline phases and a cascade of transitions with rapidly changing flux (tilt in the height language). We analyze perturbatively the vicinity of the Rokhsar-Kivelson point, showing that this model has the microscopic ingredients needed for the "devil's staircase" scenario [E. Fradkin et al., Phys. Rev. B 69, 224415 (2004)], and is therefore expected to produce fractal variations of the ground-state flux.

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T. M. Schlittler, T. Barthel, G. Misguich, J. Vidal, R. Mosseri. 2015-07-16. Phase diagram of an extended quantum dimer model on the hexagonal lattice. https://doi.org/10.1103/physrevlett.115.217202

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