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Phase Separation Dynamics in a Concentration Gradient

A. M. Lacasta·J. M. Sancho·Chuck Yeung
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Abstract

Phase separation dynamics with an initially non-uniform concentration are studied. Critical and off-critical behavior is observed simultaneously. A mechanism for an expanding phase separated region is demonstrated and the time dependence of the concentration is determined. The final equilibrium state consists of a planar interface separating one phase from the other. The evolution to this state is characterized by an experimentally observable flux, $j$, crossing this interface. We find that $j \sim t^{-2/3}$ if patterns are formed in the bulk and $j \sim t^{-1/2}$ if the bulk remains homogeneous. The results are explained in terms of scaling arguments which are confirmed numerically. (postScript figures appended to end of lateX file).

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A. M. Lacasta, J. M. Sancho, Chuck Yeung. 1994-04-21. Phase Separation Dynamics in a Concentration Gradient. https://doi.org/10.1209/0295-5075%2F27%2F4%2F007

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