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arXiv · 1406.2077

Interfaces, Strings, and a Soft Mode in the Square Lattice Quantum Dimer Model

D. Banerjee·M. Bögli·C. P. Hofmann·F. -J. Jiang·P. Widmer·U. -J. Wiese
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Abstract

The quantum dimer model on the square lattice is equivalent to a $U(1)$ gauge theory. Quantum Monte Carlo calculations reveal that, for values of the Rokhsar-Kivelson (RK) coupling $\lambda < 1$, the theory exists in a confining columnar phase. The interfaces separating distinct columnar phases display plaquette order, which, however, is not realized as a bulk phase. Static "electric" charges are confined by flux tubes that consist of multiple strands, each carrying a fractionalized flux $\frac{1}{4}$. A soft pseudo-Goldstone mode emerges around $\lambda \approx 0$, long before one reaches the RK point at $\lambda = 1$.

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D. Banerjee, M. Bögli, C. P. Hofmann, F. -J. Jiang, P. Widmer, U. -J. Wiese. 2014-06-09. Interfaces, Strings, and a Soft Mode in the Square Lattice Quantum Dimer Model. https://doi.org/10.1103/physrevb.90.245143

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