Higher-order finite-difference modal method with interface conditions for the electromagnetic analysis of gratings
Journal
Journal of Lightwave Technology
Journal Volume
30
Journal Issue
10
Pages
1393-1398
Date Issued
2012
Author(s)
Shen, C.-K.
Abstract
We present a finite-difference modal method (FDMM) combined with higher-order interface conditions to analyze the diffraction of grating structures. The generalized Douglas (GD) scheme is also adopted to further enhance the convergence. Numerical results show the FDMM generally results in faster convergence than the commonly used coupled-wave analysis (RCWA) as higher-order formulation, such as the GD with five points, is adopted in both TE and TM polarizations. The FDMM is also relatively stable in a highly conductive lossless rectangular grating, while the RCWA suffers instabilities in such a frequently studied structure.
Type
journal article