Electromagnetic simulations of metallic materials using the mapped fourier PSTD algorithm.

Previously, the regular Fourier pseudospectral time-domain (PSTD) algorithm was recognized as mainly applicable to simulations of low-contrast dielectric materials. In this paper, we discuss the difficulties in simulating high-contrast and particularly metallic materials using the Fourier PSTD method. To overcome these difficulties, we use a nonuniform grid obtained from a specially designed mapping curve that can reduce the Gibbs phenomenon in the mapped space. The convergence property of this technique is then examined. We show dramatic improvements compared with regular Fourier PSTD and finite-difference time-domain (FDTD) methods on a uniform grid. As an example application, we apply our method to the modeling of the 2D scattering of a chrome-projection lithography mask. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 569–575, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20699 [ABSTRACT FROM AUTHOR]