title: Artifact-free analysis of highly conducting binary gratings by using the Legendre polynomial expansion method.
abstract: Analysis of highly conducting binary gratings in TM polarization has been problematic as the Fourier factorization fails and thus unwanted numerical artifacts appear. The Legendre polynomial expansion method (LPEM) is employed here, and the erroneous harsh variations attributed to the violation of the inverse rule validity in applying the Fourier factorization are filtered out. In this fashion, stable and artifact-free numerical results are obtained. The observed phenomenon is clearly demonstrated via several numerical examples and is explained by inspecting the transverse electromagnetic field profile.
authors.affiliation: Integrated Photonics Laboratory, Department of Electrical Engineering, Sharif University of Technology, P.O. Box 11555-4363, Tehran, Iran.
authors.forename: Amin
authors.initials: A
authors.lastname: Khavasi
authors.forename: Khashayar
authors.initials: K
authors.lastname: Mehrany