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arXiv · 0802.2985

Evidence for a disorder driven phase transition in the condensation of 4He in aerogels

Fabien Bonnet·Thierry Lambert·Benjamin Cross·Laurent Guyon·Florence Despetis·Laurent Puech·Pierre-Etienne Wolf
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Abstract

We report on thermodynamic and optical measurements of the condensation process of $^4$He in three silica aerogels of different microstructures. For the two base-catalysed aerogels, the temperature dependence of the shape of adsorption isotherms and of the morphology of the condensation process show evidence of a disorder driven transition, in agreement with recent theoretical predictions. This transition is not observed for a neutral-catalysed aerogel, which we interpret as due to a larger disorder in this case.

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Fabien Bonnet, Thierry Lambert, Benjamin Cross, Laurent Guyon, Florence Despetis, Laurent Puech, Pierre-Etienne Wolf. 2008-02-21. Evidence for a disorder driven phase transition in the condensation of 4He in aerogels. https://doi.org/10.1209/0295-5075/82/56003

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