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arXiv · 0807.4166

Stable suspension and dispersion-induced transitions from repulsive Casimir forces between fluid-separated eccentric cylinders

Alejandro W. Rodriguez·J. N. Munday·J. D. Joannopoulos·Federico Capasso·Diego A. R. Dalvit·Steven G. Johnson
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Abstract

Using an exact numerical method for finite nonplanar objects, we demonstrate a stable mechanical suspension of a silica cylinder within a metallic cylinder separated by ethanol, via a repulsive Casimir force between the silica and the metal. We investigate cylinders with both circular and square cross sections, and show that the latter exhibit a stable orientation as well as a stable position, via a method to compute Casimir torques for finite objects. Furthermore, the stable orientation of the square cylinder is shown to undergo an unusual 45 degrees transition as a function of the separation lengthscale, which is explained as a consequence of material dispersion.

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Alejandro W. Rodriguez, J. N. Munday, J. D. Joannopoulos, Federico Capasso, Diego A. R. Dalvit, Steven G. Johnson. 2008-11-08. Stable suspension and dispersion-induced transitions from repulsive Casimir forces between fluid-separated eccentric cylinders. https://doi.org/10.1103/physrevlett.101.190404

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