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arXiv · 1303.6858

The (2+1)-d U(1) Quantum Link Model Masquerading as Deconfined Criticality

D. Banerjee·F. -J. Jiang·P. Widmer·U. -J. Wiese
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Abstract

The $(2+1)$-d U(1) quantum link model is a gauge theory, amenable to quantum simulation, with a spontaneously broken SO(2) symmetry emerging at a quantum phase transition. Its low-energy physics is described by a $(2+1)$-d $\RP(1)$ effective field theory, perturbed by a dangerously irrelevant SO(2) breaking operator, which prevents the interpretation of the emergent pseudo-Goldstone boson as a dual photon. At the quantum phase transition, the model mimics some features of deconfined quantum criticality, but remains linearly confining. Deconfinement only sets in at high temperature.

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D. Banerjee, F. -J. Jiang, P. Widmer, U. -J. Wiese. 2013-03-27. The (2+1)-d U(1) Quantum Link Model Masquerading as Deconfined Criticality. https://doi.org/10.1088/1742-5468%2F2013%2F12%2Fp12010

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