Efficient implementation of the uniaxial‐based PML media in three‐dimensional nonorthogonal coordinates with the use of the FDTD technique

In this work, a novel implementation of the uniaxial PML absorbing boundary condition in a 3D nonorthogonal space is proposed and studied. To evaluate the PML, the medium is applied to a bifilar helical waveguide structure. The effectiveness of the PML is thoroughly investigated versus the PML depth, profile, and conductivity. Results are presented for both homogeneous and inhomogeneous geometries.