Generalized plasma-like permittivity and thermal Casimir force between real metals

Abstract

The physical reasons why the Drude dielectric function is not compatible with the Lifshitz formula, as opposed to the generalized plasma-like permittivity, are presented. Essentially, the problem is connected with the finite size of metal plates. It is shown that the Lifshitz theory combined with the generalized plasma-like permittivity is thermodynamically consistent.Comment: 17 pages, iopart.cls is used, to appear in J. Phys. A: Math. Theo