Coupled-mode theory for resonant gratings with a varying period

We propose a coupled-mode theory for resonant diffraction gratings with a varying period. We consider diffractive structures, in which the reciprocal lattice vector, a quantity inversely proportional to the period, varies linearly in the direction of periodicity. It is shown that optical properties...

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Bibliographic Details
Main Authors: D.A. Bykov, E.A. Bezus, L.L. Doskolovich
Format: Article
Language:English
Published: Samara National Research University 2023-06-01
Series:Компьютерная оптика
Subjects:
Online Access:https://computeroptics.ru/eng/KO/Annot/KO47-3/470301e.html
Description
Summary:We propose a coupled-mode theory for resonant diffraction gratings with a varying period. We consider diffractive structures, in which the reciprocal lattice vector, a quantity inversely proportional to the period, varies linearly in the direction of periodicity. It is shown that optical properties of such a structure essentially depend on the period change rate. On the basis of a comparison with the results of rigorous numerical simulations using the rigorous coupled-wave analysis, high accuracy of the proposed theoretical model is demonstrated. In particular, the developed coupled-mode theory describes the broadening of the resonant peak and the appearance of secondary maxima caused by a non-zero period change rate. The obtained results can be used for the development of linear variable filters based on resonant diffraction gratings with varying parameters.
ISSN:0134-2452
2412-6179