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arXiv · 0810.1392

Aging and effective temperatures near a critical point

Sylvain Joubaud·Baptiste Percier·Artem Petrosyan·Sergio Ciliberto
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Abstract

The orientation fluctuations of the director of a liquid crystal(LC) are measured after a quench near the Fréedericksz transition, which is a second order transition driven by an electric field. We report experimental evidence that, because of the critical slowing down, the LC presents, after the quench, several properties of an aging system, such as power law scaling versus time of correlation and response functions. During this slow relaxation, a well defined effective temperature, much larger than the heat bath temperature, can be measured using the fluctuation dissipation relation.

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Sylvain Joubaud, Baptiste Percier, Artem Petrosyan, Sergio Ciliberto. 2009-03-06. Aging and effective temperatures near a critical point. https://doi.org/10.1103/physrevlett.102.130601

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