A 3-D MoM for Uniaxial Objects With an Arbitrary Optical Axis Embedded in Uniaxial Multilayers

The method of moments (MoM) for solving surface integral equations (SIEs) has been developed to simulate the electromagnetic (EM) scattering of uniaxial objects within uniaxial multilayers. Utilizing the uniaxial layered medium Green's functions (LMGFs), the Poggio–Miller–Chang–Harrington–Wu–Tsai (PMCHWT) formulation is employed to derive equivalent electric and magnetic current densities in the scatterer, thereby determining the scattered field. A notable advancement in this work is the implementation of a singularity subtraction method for the uniaxial LMGFs, specifically designed to expedite the Sommerfeld integrals. This method effectively eliminates the singularity of Green's functions in uniaxial multilayered media. Furthermore, our approach obviates the need to address the singularity associated with surface-wave poles and branch cuts in the Sommerfeld integrals. The primary contribution of this research lies in the development of MoM for analyzing uniaxial objects embedded in uniaxial multilayers, particularly when the optical axis of the scatterer is not aligned with that of the background. The accuracy and efficiency of our proposed method have been validated through several numerical experiments, with comparative analyses against results obtained using COMSOL Multiphysics.