Improved and efficient unconditionally stable complex-envelope frequency-dependent FDTD formulations based on the implicit locally one-dimensional scheme

Abstract

Improved and efficient unconditionally stable complex-envelope (CE) frequency-dependent finite-difference time-domain (FDTD) formulations, based on the implicit locally one-dimensional (LOD) scheme, are presented for modeling band-limited electromagnetic applications. The proposed formulations provide better accuracy performance than the CE implementations of previous classical LOD scheme while requiring less number of additional auxiliary variables and this will reduce both the CPU time and memory storage requirements. Moreover, the formulations allow modeling different frequency-dependent models in a straight forward manner. Numerical example carried out in a two-dimensional (2D) domain composed of Drude-Lorentz frequency-dependent material is included to show the validity of the formulations.