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Roundabout relaxation: collective excitation requires a detour to equilibrium

Hidetoshi Morita·Kunihiko Kaneko
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Abstract

Relaxation to equilibrium after strong and collective excitation is studied, by using a Hamiltonian dynamical system of one dimensional XY model. After an excitation of a domain of $K$ elements, the excitation is concentrated to fewer elements, which are made farther away from equilibrium, and the excitation intensity increases logarithmically with $K$. Equilibrium is reached only after taking this ``roundabout'' route, with the time for relaxation diverging asymptotically as $K^γ$ with $γ\approx 4.2$.

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Hidetoshi Morita, Kunihiko Kaneko. 2004-07-17. Roundabout relaxation: collective excitation requires a detour to equilibrium. https://doi.org/10.1103/physrevlett.94.087203

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