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arXiv · 1003.0430

Non-monotonic thermal Casimir force from geometry-temperature interplay

Alexej Weber·Holger Gies
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Abstract

The geometry dependence of Casimir forces is significantly more pronounced in the presence of thermal fluctuations due to a generic geometry-temperature interplay. We show that the thermal force for standard sphere-plate or cylinder-plate geometries develops a non-monotonic behavior already in the simple case of a fluctuating Dirichlet scalar. In particular, the attractive thermal force can increase for increasing distances below a critical temperature. This anomalous behavior is triggered by a reweighting of relevant fluctuations on the scale of the thermal wavelength. The essence of the phenomenon becomes transparent within the worldline picture of the Casimir effect.

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Alexej Weber, Holger Gies. 2010-03-01. Non-monotonic thermal Casimir force from geometry-temperature interplay. https://doi.org/10.1103/physrevlett.105.040403

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