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arXiv · 1112.1702

Exact Spin Liquid Ground States of the Quantum Dimer Model on the Square and Honeycomb Lattices

Hong Yao·Steven A. Kivelson
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Abstract

We study a generalized quantum hard-core dimer model on the square and honeycomb lattices, allowing for first and second neighbor dimers. At generalized RK points, the exact ground states can be constructed, and ground-state correlation functions can be equated to those of interacting 1+1 dimensional Grassmann fields. When the concentration of second neighbor dimers is small, the ground state correlations are shown to be short-ranged corresponding to a (gaped) spin liquid phase. On a 2-torus, the ground states exhibit fourfold topological degeneracy. On a finite cylinder we have found a dramatic even-odd effect depending on the circumference, and propose that this can be used as a numerical diagnostic of gapped spin-liquid phases, more generally.

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Hong Yao, Steven A. Kivelson. 2011-12-07. Exact Spin Liquid Ground States of the Quantum Dimer Model on the Square and Honeycomb Lattices. https://doi.org/10.1103/physrevlett.108.247206

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