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arXiv · 1201.6423

Dynamic relaxation of topological defect at Kosterlitz-Thouless phase transition

X. P. Qin·B. Zheng·N. J. Zhou
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Abstract

With Monte Carlo methods we study the dynamic relaxation of a vortex state at the Kosterlitz-Thouless phase transition of the two-dimensional XY model. A local pseudo-magnetization is introduced to characterize the symmetric structure of the dynamic systems. The dynamic scaling behavior of the pseudo-magnetization and Binder cumulant is carefully analyzed, and the critical exponents are determined. To illustrate the dynamic effect of the topological defect, similar analysis for the the dynamic relaxation with a spin-wave initial state is also performed for comparison. We demonstrate that a limited amount of quenched disorder in the core of the vortex state may alter the dynamic universality class. Further, theoretical calculations based on the long-wave approximation are presented.

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X. P. Qin, B. Zheng, N. J. Zhou. 2012-01-31. Dynamic relaxation of topological defect at Kosterlitz-Thouless phase transition. https://doi.org/10.1088/1751-8113/44/34/345005

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