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arXiv · 2206.01854

Semi-vortices and cluster-vorticity: new concepts in the Berezinskii-Kosterlitz-Thouless phase transition

Brandon Gómez Bravo·Bryan D. Juárez Hernández·Wolfgang Bietenholz
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Abstract

The Berezinskii-Kosterlitz-Thouless (BKT) essential phase transition in the 2d XY model is revisited. Its mechanism is usually described by the (un)binding of vortex--anti-vortex (V--AV) pairs, which does, however, not provide a clear-cut quantitative criterion for criticality. Known sharp criteria are the divergence of the correlation length and a discontinuity of the helicity modulus. Here we propose and probe a new criterion: it is based on the concepts of semi-vortices and cluster vorticity, which are formulated in the framework of the multi-cluster algorithm that we use to simulate the 2d XY model.

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Brandon Gómez Bravo, Bryan D. Juárez Hernández, Wolfgang Bietenholz. 2022-06-03. Semi-vortices and cluster-vorticity: new concepts in the Berezinskii-Kosterlitz-Thouless phase transition. https://doi.org/10.31349/suplrevmexfis.3.020724

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