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Updated: Feb 10, 2026

Fabrication of Zero Mode Waveguides for High Concentration Single Molecule Microscopy
Published on: May 12, 2020
Analysis of photonic crystal waveguide gratings with coupled-mode theory and a finite-element method
Takeshi Fujisawa1, Masanori Koshiba
1Division of Media and Network Technologies, Hokkaido University, Sapporo, Japan. fujisawa@dpo7.ice.eng.hokudai.ac.jp
Abstract:
Both rod and air-hole types of photonic crystal waveguide gratings are proposed and their coupling coefficients and transmission characteristics are effectively investigated by using a simple coupled-mode theory combined with a finite-element method. The results obtained are compared with the results obtained by using a full numerical simulation method. A new definition for unperturbed waveguides is introduced to obtain accurate coupling coefficients. It is shown that, by using a pi-phase-shifted waveguide structure in the case of an air-hole type of photonic crystal waveguide grating, the coupling coefficient is strongly enhanced. The accuracy of the method is discussed through numerical examples of high-index-contrast waveguide gratings.
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