Optical-approximation analysis of sidewall-spacing effects on the force between two squares with parallel sidewalls
Abstract
Using the ray-optics approximation, we analyze the Casimir force in a two dimensional domain formed by two metallic blocks adjacent to parallel metallic sidewalls, which are separated from the blocks by a finite distance h. For h > 0, the ray-optics approach is not exact because diffraction effects are neglected. Nevertheless, we show that ray optics is able to qualitatively reproduce a surprising effect recently identified in an exact numerical calculation: the force between the blocks varies non-monotonically with h. In this sense, the ray-optics approach captures an essential part of the physics of multi-body interactions in this system, unlike simpler pairwise-interaction approximations such as PFA. Furthermore, by comparison to the exact numerical results, we are able to quantify the impact of diffraction on Casimir forces in this geometry.
Cite
@article{arxiv.0709.0699,
title = {Optical-approximation analysis of sidewall-spacing effects on the force between two squares with parallel sidewalls},
author = {Saad Zaheer and Alejandro W. Rodriguez and Steven G. Johnson and Robert L. Jaffe},
journal= {arXiv preprint arXiv:0709.0699},
year = {2011}
}