GREEN DYADIC FOR A CLASS OF NONRECIPROCAL BIANISOTROPIC MEDIA

The possibility of finding nn analytic Green dyadic expression for a c lass of bianisotropic media, defined by the relations <(epsilon)over b ar> = <(tau mu)over bar>(T), <(xi)over bar> = x x (I) over bar + xi uu , and <(zeta)over bar> = z x (I) over bar + xi uu between the medium p arame ter dyadics, is studied. It is shown that the determinant of the dyadic Helmholtz operator, an operator of fourth order, can be expres sed as a product of two second-order operators. A method for finding t he solution for the Green dyadic in the form of infinite series in ter ms of powers of the dimensionless parameter xi xi/ mu(0)epsilon(0) is given. For small values of the parameter, a two-term approximation is seen to take a simple analytic form. As an Appendix, another approach through the Fourier transformation is briefly discussed. Dyadic formal ism is applied throughout in the analysis. (C) 1998 John Wiley & Sons, Inc.