TF/SF Boundary and PML–ABC for an Unconditionally Stable FDTD Method

This letter proposes a total-field/scattered-field (TF/SF) formulation and perfectly matched layer (PML) absorbing boundary condition for the unconditionally stable finite-difference time-domain (FDTD) method based on weighted Laguerre polynomials (WLPs). This approach provides the computational flexibility in electromagnetic scattering and improved performance yet maintains unconditional stable. Numerical results show the TF/SF connecting boundary and PML are effective in the WLP-FDTD method for scattering