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arXiv · 0803.0738

Thermal Casimir vs Casimir-Polder forces: Equilibrium and non-equilibrium forces

Stefan Yoshi Buhmann·Stefan Scheel
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Abstract

We critically discuss the common belief that the thermal Casimir-Polder force can always be represented as a Matsubara sum, as it is true for the Casimir force. On the contrary, an exact treatment of the atom-field coupling reveals that for a ground-state atom, terms associated with virtual-photon absorption contribute to the force which are identified as a signature of non-equilibrium dynamics. Even the equilibrium force on a thermalized atom or molecule may be overestimated when using the ground-state polarizability instead of its thermal counterpart.

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Stefan Yoshi Buhmann, Stefan Scheel. 2008-08-14. Thermal Casimir vs Casimir-Polder forces: Equilibrium and non-equilibrium forces. https://doi.org/10.1103/physrevlett.100.253201

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