Open AccessBound states in the continuum in abruptly terminated dielectric slab waveguides
Author(s) -
Evgeni A. Bezus,
Dmitry A. Bykov,
Leonid L. Doskolovich
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1461/1/012204
Subject(s) - slab , optics , dielectric , physics , waveguide , reflection (computer programming) , total internal reflection , symmetry (geometry) , bound state , ridge , geometry , quantum mechanics , geology , mathematics , computer science , paleontology , geophysics , programming language
We demonstrate that dielectric slab waveguides terminated with a dielectric ridge (i.e. with a slab waveguide segment having a greater thickness) support high-Q resonances and bound states in the continuum (BICs). The resonances and BICs take place at oblique incidence of TE-polarized guided modes in the total internal reflection geometry, when all the incident radiation is reflected at the end facet of the ridge and is not scattered out of the waveguide. We derive a simple coupled-wave model rigorously proving the BIC existence and predicting its locations. The predictions of the model are in an excellent agreement with the results of the rigorous numerical simulations. We also discuss the influence of the symmetry of the structure on the BIC existence. The obtained results may be useful for the design of novel integrated nanophotonic devices.