LATERAL CASIMIR FORCE BETWEEN DEEPLY CORRUGATED DIELECTRIC AND METALLIC PLATES

We study the lateral Casimir force between corrugated dielectric plates. We use the dielectric contrast perturbation theory [R. Golestanian, Phys. Rev. Lett.95, 230601, (2005)], which allows us to consider arbitrary deformations with large amplitudes. We consider sinusoidal, rectangular, and sawtooth corrugations, for samples made of silicon and gold. We use the plasma and Drude–Lorentz models for the permittivity of gold and silicon, respectively. For these geometries and materials, the lateral Casimir force is not a sinusoidal function of the relative lateral displacement of plates when the gap between the plates in comparable with the depth of the corrugations. Our results facilitate the design of miniaturized devices based on lateral Casimir forces.

Generalized Electromagnetic Energy Density in Time-Dependent Composite Media

The Lorentz medium model for magnetization is modification, through which the whole Lorentz models become more symmetric one than traditional forms used in [3-5]. The modification can also have the deduction for more general Poynting’ theorem in dispersive media became a regular procedure. As an application, those forms of energy density in [4, 5] are special cases of generalized one shown in the letter under the establishment conditions for time-independent situation.