Simple Approach to Electromagnetic Scattering by Small Radially Inhomogeneous Spheres

In this paper, we use the invariant embedding technique to solve the problem of plane electromagnetic (EM) wave scattering by a nonuniform object with spherically symmetric distributions of dielectric and magnetic susceptibilities. Assuming that the size of the object is smaller or comparable with the vacuum wavelength, we consider a simple and effective approach to restore the EM fields inside the object and the scattering and absorption cross sections. The method is based on exact solutions of Maxwell's equations and provides no limitations on the wavelengths inside the object. Therefore, it can be used to study complex cases, including those related to local amplification and absorption of waves in inhomogeneous resonant media.