Implementation of rigorous differential diffraction theory

This contribution reports on the progress in the implementation of the differential theory of gratings. This implementation is based on the formalism of Nevière and Popov [1] and features the correct Fourier factorization after Li [2]. The effect of numerical contamination is suppressed by use of the S-matrix algorithm, which also opens the possibility to model deep diffractive structures. The diffracted field of several kinds of profiles can be calculated: binary structures, trapezoidal (blaze) and arbitrary (parametrization using cubic splines). The principles of the simulation code are presented, as well as results which are compared to other techniques (IESMP, [3]). In an outlook the possibilities of using differential theory to model nonperiodic structures are discussed. [1] M. Nevière and E. Popov: Light Propagation in Periodic Media, Marcel Dekker, New York, 2003 [2] L. Li, J. Opt. Soc. Am. A 13,1870 (1996) [3] B. Kleemann: Elektromagnetische Analys von Oberflächengittern von IR bis XUV mittels einer parametrisierten Randintegralmethode: Theorie, Vergleich und Anwendungen, Dissertation, TU Ilmenau, 2002