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arXiv · 1206.6034

Electrostatic patch effects in Casimir force experiments performed in the sphere-plane geometry

R. O. Behunin·Y. Zeng·D. A. R. Dalvit·S. Reynaud
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Abstract

Patch potentials arising from the polycrystalline structure of material samples may contribute significantly to measured signals in Casimir force experiments. Most of these experiments are performed in the sphere-plane geometry, yet, up to now all analysis of patch effects has been taken into account using the proximity force approximation which, in essence, treats the sphere as a plane. In this paper we present the exact solution for the electrostatic patch interaction energy in the sphere- plane geometry, and derive exact analytical formulas for the electrostatic patch force and minimizing potential. We perform numerical simulations to analyze the distance dependence of the minimizing potential as a function of patch size, and quantify the sphere-plane patch force for a particular patch layout. Once the patch potentials on both surfaces are measured by dedicated experiments our formulas can be used to exactly quantify the sphere-plane patch force in the particular experimental situation.

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R. O. Behunin, Y. Zeng, D. A. R. Dalvit, S. Reynaud. 2012-06-26. Electrostatic patch effects in Casimir force experiments performed in the sphere-plane geometry. https://doi.org/10.1103/physreva.86.052509

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