Loading...

Fast estimation of propagation constants in crossed gratings

Faghihifar, E ; Sharif University of Technology | 2020

441 Viewed
  1. Type of Document: Article
  2. DOI: 10.1088/2040-8986/ab6042
  3. Publisher: IOP Publishing Ltd , 2020
  4. Abstract:
  5. Fourier-based modal methods are among the most effective numerical tools for the accurate analysis of crossed gratings. However, leading to computationally expensive eigenvalue equations significantly restricts their applicability, particularly when large truncation orders are required. The resultant eigenvalues are the longitudinal propagation constants of the grating and play a key role in applying the boundary conditions, as well as in the convergence and stability analyses. This paper aims to propose simple techniques for the fast estimation of propagation constants in crossed gratings, predominantly with no need to solve an eigenvalue equation. In particular, we show that for regular optical gratings comprised of lossless dielectrics, nearly every propagation constant appears on the main diagonal of the modal matrix. © 2019 IOP Publishing Ltd
  6. Keywords:
  7. Eigen-value estimation ; Propagation constant ; Eigenvalues and eigenfunctions ; Numerical methods ; Convergence and stability analysis ; Crossed gratings ; Eigen-value ; Eigenvalue equations ; Fourier modal method ; Longitudinal propagation constant ; Lossless dielectrics ; Modal analysis
  8. Source: Journal of Optics (United Kingdom) ; Volume 22, Issue 2 , 2020
  9. URL: https://iopscience.iop.org/article/10.1088/2040-8986/ab6042