Leaky mode analysis using complex infinite elements

Abstract

We propose a novel numerically efficient model for accurate characterization of leaky modes in optical waveguides. Within the context of finite elements, the mesh boundaries are truncated using complex infinite elements (CIEs). The CIE is based on adopting the homogeneous solution of the wave equation with the shape function of infinite elements to accurately and physically model semi-infinite subdomains instead of placing an artificial layer such as PML. The proposed treatment can be easily implemented and requires less computational resources compared to other conventional mesh truncation methods. The accuracy and rigor of our approach are demonstrated through studying different leaky waveguides’ configurations.