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arXiv · 0904.4241

On the Theory of Casimir-Polder Forces

Bo-Sture Skagerstam·Per Kristian Rekdal·Asle Heide Vaskinn
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Abstract

We consider the energy shift for an atom close to a non-magnetic body with a magnetic moment coupled to a quantized magnetic field. The corresponding repulsive Casimir-Polder force is obtained for a perfect conductor, a metal, a dielectric medium, with dielectric properties modeled by a Drude formula, and a superconductor at zero temperature. The dielectric properties of the superconductor is obtained by making use of the Mattis-Bardeen linear response theory and we present some useful expressions for the low-frequency conductivity. The quantum dynamics with a given initial state is discussed in terms of the well-known Weisskopf-Wigner theory and is compared with corresponding results for a electric dipole coupling. The results obtained are compatible with a conventional master equation approach. In order to illustrate the dependence on geometry and material properties, numerical results are presented for the ground state using a two-level approximation.

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Bo-Sture Skagerstam, Per Kristian Rekdal, Asle Heide Vaskinn. 2009-09-05. On the Theory of Casimir-Polder Forces. https://doi.org/10.1103/physreva.80.022902

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