Department of Physics Papers

Document Type

Journal Article

Date of this Version

11-10-2010

Comments

Suggested Citation:
Zaheer, S., Rahi, S.J., Emig, T. and Jaffe, R.L. (2010). "Casimir potential of a compact object enclosed by a spherical cavity." Physical Review A. 82, 052507.

© 2010 The American Physical Society
http://dx.doi.org/10.1103/PhysRevA.82.052507.

Abstract

We study the electromagnetic Casimir interaction of a compact object contained inside a closed cavity of another compact object. We express the interaction energy in terms of the objects’ scattering matrices and translation matrices that relate the coordinate systems appropriate to each object. When the enclosing object is an otherwise empty metallic spherical shell, much larger than the internal object, and the two are sufficiently separated, the Casimir force can be expressed in terms of the static electric and magnetic multipole polarizabilities of the internal object, which is analogous to the Casimir-Polder result. Although it is not a simple power law, the dependence of the force on the separation of the object from the containing sphere is a universal function of its displacement from the center of the sphere, independent of other details of the object’s electromagnetic response. Furthermore, we compute the exact Casimir force between two metallic spheres contained one inside the other at arbitrary separations. Finally, we combine our results with earlier work on the Casimir force between two spheres to obtain data on the leading-order correction to the proximity force approximation for two metallic spheres both outside and within one another.

Keywords

Casimir force

Date Posted: 21 December 2010

This document has been peer reviewed.