Comment on A PML-FDTD formulation for the simulation of optical structures

Abstract

The focus of this comment is to discuss an important point regarding the derivation of the wave equation in the perfectly matched layer (PML). It is demonstrated that the distance dependency of the PML conductivity profile should be taken into consideration when deriving the wave equation in the PML region. Significant improvements in the absorbing performance are achieved with a small number of PML layers. A numerical test is carried out in one dimension to validate the proposed formulations. (C) 2003 Wiley Periodicals, Inc.