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Scaling Function for the Diffusion Coefficient of a Critical Fluid in a Finite Geometry

Palash Das·Jayanta K. Bhattacharjee
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Abstract

The long wavelength diffusion coefficient of a critical fluid confined between two parallel plates separated by a distance L is strongly affected by the finite size. Finite size scaling leads us to expect that the vanishing of the diffusion coefficient as ξ^{-1} for ξ< >L. We show that this is not strictlytrue. There is a logarthmic scaling violation. We construct a Kawasaki like scaling function that connects the thermodynamic regime to the extreme critical (ξ>>L) regime.

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Palash Das, Jayanta K. Bhattacharjee. 2003-07-03. Scaling Function for the Diffusion Coefficient of a Critical Fluid in a Finite Geometry. https://doi.org/10.1103/physreve.69.036116

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