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arXiv · 0704.1890

Computation and visualization of Casimir forces in arbitrary geometries: non-monotonic lateral forces and failure of proximity-force approximations

Alejandro Rodriguez·Mihai Ibanescu·Davide Iannuzzi·Federico Capasso·John D. Joannopoulos·Steven G. Johnson
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Abstract

We present a method of computing Casimir forces for arbitrary geometries, with any desired accuracy, that can directly exploit the efficiency of standard numerical-electromagnetism techniques. Using the simplest possible finite-difference implementation of this approach, we obtain both agreement with past results for cylinder-plate geometries, and also present results for new geometries. In particular, we examine a piston-like problem involving two dielectric and metallic squares sliding between two metallic walls, in two and three dimensions, respectively, and demonstrate non-additive and non-monotonic changes in the force due to these lateral walls.

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Alejandro Rodriguez, Mihai Ibanescu, Davide Iannuzzi, Federico Capasso, John D. Joannopoulos, Steven G. Johnson. 2007-04-15. Computation and visualization of Casimir forces in arbitrary geometries: non-monotonic lateral forces and failure of proximity-force approximations. https://doi.org/10.1103/physrevlett.99.080401

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