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arXiv · 0909.5030

Phase structure of $Z_2$ gauge theories for frustrated antiferromagnets in two dimensions

K. Nakane·A. Shimizu·I. Ichinose
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Abstract

In this paper, we study phase structure of $Z_2$ lattice gauge theories that appear as an effective field theory describing low-energy properties of frustrated antiferromagnets in two dimensions. Spin operators are expressed in terms of Schwinger bosons, and an emergent U(1) gauge symmetry reduces to a $Z_2$ gauge symmetry as a result of condensation of a bilinear operator of the Schwinger boson describing a short-range spiral order. We investigated the phase structure of the gauge theories by means of the Monte-Carlo simulations, and found that there exist three phases, phase with a long-range spiral order, a dimer state, and a spin liquid with deconfined spinons. Detailed phase structure and properties of phase transitions depend on details of the models.

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K. Nakane, A. Shimizu, I. Ichinose. 2009-12-11. Phase structure of $Z_2$ gauge theories for frustrated antiferromagnets in two dimensions. https://doi.org/10.1103/physrevb.80.224425

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