Casimir Forces in Non-Homogeneous Planar and Spherical Systems

C. Villarreal, R. Esquivel-Sirvent, L. Mochan, and C. Noguez

Institute de Fisica
Universidad Autonoma de Mexico
Apartado Postal 20-364
Mexico, 01000, D.F.

With the advent of new nanotechonologies and experimental techniques exact measurements of the Casimir forces are now feasible. Within that context, we calculate three-dimensional Casimir forces for non-homogeneous materials. In the case of heterogeneous slabs, we compare with experimental results obtained using atomic force microscopes. In addition, we determine the Casimir force between a spherical dielectric particle and a planar substrate in the non-retarded approximation by including multipolar couplings between the particle and the substrate. Our results generalize the dipolar approximation of Casimir and Polder. We discuss the applicability of the proximity force theorem.