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arXiv · 1905.04170

Bound States in the Continuum and Fano Resonances in the Dirac Cone Spectrum

E. N. Bulgakov·D. N. Maksimov
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Abstract

We consider light scattering by two dimensional arrays of high-index dielectric spheres arranged into the triangular lattice. It is demonstrated that in the case a triple degeneracy of resonant leaky modes in the Gamma-point the scattering spectra exhibit a complicated picture of Fano resonances with extremely narrow line-width. The Fan features are explained through coupled mode theory for a Dirac cone spectrum as a signature of optical bound states in the continuum (BIC). It is found that the standing wave in-Gamma BIC induces a ring of off-Gamma BICs due to different scaling laws for real and imaginary parts of the resonant eigenfrequencies in the Dirac cone spectrum. A quantitative theory of the spectra is proposed.

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E. N. Bulgakov, D. N. Maksimov. 2019-05-10. Bound States in the Continuum and Fano Resonances in the Dirac Cone Spectrum. https://doi.org/10.1364/josab.36.002221

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