Work fluctuations in a nematic liquid crystal
نویسنده
چکیده
The orientation fluctuations of the director of a liquid crystal are measured, by a sensitive polarization interferometer, close to the Fréedericksz transition, which is a second order transition driven by an electric field. Using mean field theory, we define the work injected into the system by a change of the electric field and we calibrate it using Fluctuation-Dissipation Theorem. We show that the work fluctuations satisfy the Transient Fluctuation Theorem. An analytical justification of this result is given. The open problems for the out of equilibrium case are finally discussed. PACS numbers: 05.40.-a,05.70.xz-a
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