A theory of dielectric fluid films between nanostructures

In this paper a theory of dielectric fluid films between nanostructures is developed by using the theory of nonlocal electromagnetic fluids so that the nonlocal hydrodynamic force, the Lifshitz force and solvation forces can be treated systematically within the realm of continuum mechanics. In order for a continuum model to account for these surface forces of molecular origin without ad hoc assumptions, it should be endowed with a theoretical framework in which not only to represent the inner structures of fluids but to inherently possess a rational basis to merge with the Lifshitz theory without losing its rigor and also to accommodate other types of surface forces. The proposed nonlocal continuum model is formulated as such and can be adapted to all separations for which the Lifshitz theory is valid. It is applied, as an example problem, to the case of a plane-sphere configuration in the non-retarded van der Waals limit where solvation forces manifest themselves.