Microscopic cut-off dependence of an entropic force in interface propagation of stochastic order parameter dynamics

Yutaro Kado; Shin-ichi Sasa

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arXiv · 2304.03554

Microscopic cut-off dependence of an entropic force in interface propagation of stochastic order parameter dynamics

Yutaro Kado·Shin-ichi Sasa

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Abstract

The steady propagation of a $(d-1)$-dimensional planer interface in $d$-dimensional space is studied by analyzing mesoscopic non-conserved order parameter dynamics with two local minima under the influence of thermal noise. In this analysis, an entropic force generating interface propagation is formulated using a perturbation method. It is found that the entropic force singularly depends on an ultraviolet cut-off when $d \ge 2$. The theoretical calculation is confirmed by numerical simulations with $d=2$. The result means that an experimental measurement of the entropic force provides an estimation of the microscopic cut-off of the mesoscopic description.

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Yutaro Kado, Shin-ichi Sasa. 2023-04-07. Microscopic cut-off dependence of an entropic force in interface propagation of stochastic order parameter dynamics. https://arxiv.org/abs/2304.03554

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