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arXiv · 1006.5287

Phase diagram of the fully frustrated transverse-field Ising model on the honeycomb lattice

T. Coletta·J. -D. Picon·S. E. Korshunov·F. Mila
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Abstract

Motivated by the current interest in the quantum dimer model on the triangular lattice, we investigate the phase diagram of the closely related fully-frustrated transverse field Ising model on the honeycomb lattice using classical and semi-classical approximations. We show that, in addition to the fully polarized phase at large field, the classical model possesses a multitude of phases that break the translational symmetry which in the dimer language, correspond to a plaquette phase and a columnar phase separated by an infinite cascade of mixed phases. The modification of the phase diagram by quantum fluctuations has been investigated in the context of linear spin-wave theory. The extrapolation of the semiclassical energies suggests that the plaquette phase extends down to zero field for spin 1/2, in agreement with the $\sqrt{12}\times\sqrt{12}$ phase of the quantum dimer model on the triangular lattice with only kinetic energy.

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T. Coletta, J. -D. Picon, S. E. Korshunov, F. Mila. 2010-12-08. Phase diagram of the fully frustrated transverse-field Ising model on the honeycomb lattice. https://doi.org/10.1103/physrevb.83.054402

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