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arXiv · 0907.2654

Casimir-Polder interaction between an atom and a small magnetodielectric sphere

Agnes Sambale·Stefan Yoshi Buhmann·Stefan Scheel
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Abstract

On the basis of macroscopic quantum electrodynamics and point-scattering techniques, we derive a closed expression for the Casimir-Polder force between a ground-state atom and a small magnetodielectric sphere in an arbitrary environment. In order to allow for the presence of both bodies and media, local-field corrections are taken into account. Our results are compared with the known van der Waals force between two ground-state atoms. To continuously interpolate between the two extreme cases of a single atom and a macroscopic sphere, we also derive the force between an atom and a sphere of variable radius that is embedded in an Onsager local-field cavity. Numerical examples illustrate the theory.

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Agnes Sambale, Stefan Yoshi Buhmann, Stefan Scheel. 2009-07-15. Casimir-Polder interaction between an atom and a small magnetodielectric sphere. https://doi.org/10.1103/physreva.81.012509

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