ANALYSIS OF DIELECTRIC GRATINGS OF ARBITRARY PROFILES AND THICKNESSES

An efficient and stable eigenmode method is presented for the analysis of dielectric gratings of arbitrary profiles and thicknesses. The solution is expanded in terms of multiple sets of modes. The method differs from the usual eigenmode methods in that mode couplings are achieved through an iterative one-way wave multiple reflection series requiring only matrix-vector multiplications. The solution is computationally simple, has a physical interpretation, and remains stable for gratings of any thickness. Numerical results agree well with those of previous methods.