Analysis of an optical polarizer based on laminated-cover waveguide

A new simple form of a rib-waveguide polarizer is proposed and investigated. The cladding consists of a dielectric multilayer based on Si and SiO₂; the core is a single-mode MO (magnetooptic) channel waveguide in Ce-substituted Yttrium Iron Garnet (YIG). The TM-passing property of the anisotropic cover filters out the unwanted polarization. The authors first develop a modal analysis of the rib waveguide and then perform a full-wave modeling of the polarizer by means of the transmission-line matrix integral equation (TLMIE) method. The TLMIE is an efficient three-dimensional (3-D) hybrid technique that combines the advantages of the numerical transmission-line matrix (TLM) method in dense finite regions, and those of the analytical Green´s functions where available. The TLMIE method validates the modal analysis, yields an accurate physical insight of the polarization selection, and, it provides a tool for the optimization of the device