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arXiv · 1108.5966

Criticality and phase separation in a two-dimensional binary colloidal fluid induced by the solvent critical behavior

O. Zvyagolskaya·A. J. Archer·C. Bechinger
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Abstract

We present an experimental and theoretical study of the phase behavior of a binary mixture of colloids with opposite adsorption preferences in a critical solvent. As a result of the attractive and repulsive critical Casimir forces, the critical fluctuations of the solvent lead to a further critical point in the colloidal system, i.e. to a critical colloidal-liquid--colloidal-liquid demixing phase transition which is controlled by the solvent temperature. Our experimental findings are in good agreement with calculations based on a simple approximation for the free energy of the system.

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O. Zvyagolskaya, A. J. Archer, C. Bechinger. 2011-08-30. Criticality and phase separation in a two-dimensional binary colloidal fluid induced by the solvent critical behavior. https://doi.org/10.1209/0295-5075/96/28005

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