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arXiv · 1610.00605

Action minimization and macroscopic interface motion under forced displacement

P. Birmpa·D. Tsagkarogiannis
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Abstract

We study an one dimensional model where an interface is the stationary solution of a mesoscopic non local evolution equation which has been derived by a microscopic stochastic spin system. Deviations from this evolution equation can be quantified by obtaining the large deviations cost functional from the underlying stochastic process. For such a functional, derived in a companion paper, we investigate the optimal way for a macroscopic interface to move from an initial to a final position distant by R within fixed time T. We find that for small values of R/T the interface moves with a constant speed, while for larger values there appear nucleations of the other phase ahead of the front.

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P. Birmpa, D. Tsagkarogiannis. 2016-10-03. Action minimization and macroscopic interface motion under forced displacement. https://arxiv.org/abs/1610.00605

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