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arXiv · 0706.1674

Fluctuations of the Casimir-Polder force between an atom and a conducting wall

R. Messina·R. Passante
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Abstract

We consider the quantum fluctuations of the Casimir-Polder force between a neutral atom and a perfectly conducting wall in the ground state of the system. In order to obtain the atom-wall force fluctuation we first define an operator directly associated to the force experienced by the atom considered as a polarizable body in an electromagnetic field, and we use a time-averaged force operator in order to avoid ultraviolet divergences appearing in the fluctuation of the force. This time-averaged force operator takes into account that any measurement involves a finite time. We also calculate the Casimir-Polder force fluctuation for an atom between two conducting walls. Experimental observability of these Casimir-Polder force fluctuations is also discussed, as well as the dependence of the relative force fluctuation on the duration of the measurement.

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R. Messina, R. Passante. 2007-06-12. Fluctuations of the Casimir-Polder force between an atom and a conducting wall. https://doi.org/10.1103/physreva.76.032107

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