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arXiv · 1106.5015

Temperature-independent Casimir-Polder forces in arbitrary geometries

Simen Å. Ellingsen·Stefan Yoshi Buhmann·Stefan Scheel
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Abstract

We show that the Casimir-Polder potential of a particle in an energy eigenstate at nonretarded distance from a well-conducting body of arbitrary shape is independent of the environment temperature. This is true even when the thermal photon numbers at the relevant atomic transition energies are large. A compact expression is obtained for the temperature-independent potential, which can greatly simplify calculations in nontrivial geometries for experimentally relevant systems such as Rydberg atoms and polar molecules. We give criteria for the validity of our temperature-independent result. They are illustrated by numerical studies of a particle near a gold sphere or inside a gold cylindrical cavity.

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Simen Å. Ellingsen, Stefan Yoshi Buhmann, Stefan Scheel. 2011-06-24. Temperature-independent Casimir-Polder forces in arbitrary geometries. https://doi.org/10.1103/physreva.84.060501

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