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Deconfinement in the Two Dimensional XY Model

H. A. Fertig
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Abstract

The unbinding of vortex-antivortex pairs for the classical two-dimensional XY model in a magnetic field is studied. A single such pair is connected by a string of overturned spins, leading to linear confinement. We show that this system supports two phase transitions, one in which closed strings proliferate, and a second in which vortices unbind. The transitions are shown to be dual to one another, and are remarkably continuous. Possible consequences for a variety of systems are discussed.

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H. A. Fertig. 2002-06-19. Deconfinement in the Two Dimensional XY Model. https://doi.org/10.1103/physrevlett.89.035703

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