Green dyadic calculations for inhomogeneous optical media

A difference equation obtained for the reassociated Green dyadic formalism is exploited to obtain solutions for the case of a multilayered dielectric medium. Computation of limits as layers become progressively thinner leads to a parallel development for the case of a dielectric varying continuously in a single direction. A demonstration example then shows how discrete and continuous techniques can be combined into a hybrid formulation. Finally, numerical computations are presented for the simple case of a dipole, illustrating convergence of the difference equation solutions to the differential equation solution. (C) 2000 Optical Society of America [S0740-3232(00)01706-3].