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arXiv · 1309.1243

Condensation of helium in aerogels and athermal dynamics of the Random Field Ising Model

Geoffroy Aubry·Fabien Bonnet·Mathieu Melich·Laurent Guyon·Panayotis Spathis·Florence Despetis·Pierre-Etienne Wolf
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Abstract

High resolution measurements reveal that condensation isotherms of $^4$He in a silica aerogel become discontinuous below a critical temperature. We show that this behaviour does not correspond to an equilibrium phase transition modified by the disorder induced by the aerogel structure, but to the disorder-driven critical point predicted for the athermal out-of-equilibrium dynamics of the Random Field Ising Model. Our results evidence the key role of non-equilibrium effects in the phase transitions of disordered systems.

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Geoffroy Aubry, Fabien Bonnet, Mathieu Melich, Laurent Guyon, Panayotis Spathis, Florence Despetis, Pierre-Etienne Wolf. 2014-09-07. Condensation of helium in aerogels and athermal dynamics of the Random Field Ising Model. https://doi.org/10.1103/physrevlett.113.085301

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