On the surface effect in thin molecular or composite layers

¹ Physics Department, St. Petersburg State Institute for Fine Mechanics and Optics, Sablinskaya 14, 197101 St. Petersburg, Russia
² Electromagnetics Laboratory, Helsinki University of Technology, P.O. Box 3000, 02015 Hut, Finland
³ Department of Electromagnetic Theory, Royal Institute of Technology, Osquldas v. 6, 10044 Stockholm, Sweden

Corresponding author: sergei@eml.hut.fi

Received: 10 September 1999
Revised: 11 January 2000
Accepted: 20 January 2000
Published online: 15 March 2000

Abstract

The electromagnetic properties of thin dielectric or composite layers are considered. We study the case when the thickness d of a slab is so small that only a few particles forming the effective medium are located on the interval d. A novel approach to the quasistatic modelling of the local field acting on a particle is suggested. In this case the local "permittivity" near the upper and lower surfaces of the slab differs from the bulk permittivity of the same material. This can influence the reflection and transmission properties of the slab. Even if the particles are isotropically polarizable or are randomly oriented in the slab volume, this thin structure has anisotropic (uniaxial) electromagnetic properties.