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arXiv · 1410.5599

Chaotic properties of spin lattices near second-order phase transitions

A. S. de Wijn·B. Hess·B. V. Fine
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Abstract

We perform a numerical investigation of the Lyapunov spectra of chaotic dynamics in lattices of classical spins in the vicinity of second-order ferromagnetic and antiferromagnetic phase transitions. On the basis of this investigation, we identify a characteristic of the shape of the Lyapunov spectra, the "G-index", which exhibits a sharp peak as a function of temperature at the phase transition, provided the order parameter is capable of sufficiently strong dynamic fluctuations. As a part of this work, we also propose a general numerical algorithm for determining the temperature in many-particle systems, where kinetic energy is not defined.

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A. S. de Wijn, B. Hess, B. V. Fine. 2016-01-07. Chaotic properties of spin lattices near second-order phase transitions. https://doi.org/10.1103/physreve.92.062929

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