Phase transition of Two-timescale Two-temperature Spin-lattice Gas Model

C. H. Nakajima; K. Hukushima

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arXiv · 0807.4601

Phase transition of Two-timescale Two-temperature Spin-lattice Gas Model

C. H. Nakajima·K. Hukushima

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Abstract

We study phase transition of a nonequilibrium statistical-mechanical model, in which two degrees of freedom with different time scales separated from each other touch to their own heat bath. A general condition for finding anomalous negative latent heat recently discovered is derived a from thermodynamic argument. As a specific example, phase diagram of a spin-lattice gas model is studied based on a mean-field analysis with replica method. While configurational variables are spin and particle in this model, it is found that the negative latent heat appears in a parameter region of the model, irrespective of the order of their time scale. Qualitative differences in the phase diagram are also discussed.

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C. H. Nakajima, K. Hukushima. 2008-07-29. Phase transition of Two-timescale Two-temperature Spin-lattice Gas Model. https://arxiv.org/abs/0807.4601

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