Multilayer anisotropic bi-periodic diffraction gratings

The formalism of Rokushima and Yamakita [J. Opt. Sec. Am. 73 (1983) 901] tr eating the diffraction on planar multilayered 1D anisotropic gratings is ex tended to the diffraction on anisotropic 2D multilayer grating structures b i-periodic in the plane parallel to the interfaces. In addition to the obli que incidence of plane waves, the case of normal incidence is also treated. The goal of the paper is to provide a basis for the formal analysis of 2D patterned multilayers with natural or induced anisotropies. For example, su ch structures are of interest in the design of new magnetic and magneto-opt ic devices. In view of the fact that the anisotropies have often a negligib le effect on the energy distribution among diffracted modes with respect to the isotropic case the optical response is alternatively expressed in term s of the ellipsometric parameters of diffracted waves. The present analysis represents generalization of the problem of electromagnetic wave interacti ons in planar multilayers consisting of layers characterized by a general p ermittivity tenser treated by Yeh [J. Opt. Sec. Am. 69 (1979) 742].