Coupled-wave formalism for bound states in the continuum in guided-mode resonant gratings

Abstract

We present simple yet extremely accurate coupled-wave models describing the formation of bound states in the continuum (BICs) in 1D-periodic guided-mode resonant gratings (GMRGs) consisting of a slab waveguide layer with a binary grating attached to one or both of its interfaces. Using these models, we obtain simple closed-form expressions predicting the locations of the BICs and quasi-BICs in the $\omega$-$k_x$ parameter space. We study two mechanisms of the BIC formation: coupling between two counter-propagating guided modes and coupling between a guided mode and a Fabry-Pérot mode. The BIC conditions for the two considered mechanisms are formulated in terms of the scattering coefficients of the binary grating. The predictions of the presented models are in excellent agreement with the results of rigorous numerical simulations obtained using the Fourier modal method.

9 pages, 5 figures

References in corpus (4)

• Topological nature of bound states in the radiation continuum
• Bloch bound states in the radiation continuum in a periodic array of dielectric rods
• Numerical methods for calculating poles of the scattering matrix with applications in grating theory
• Polarized bound state in the continuum and resonances with tunable Q-factor in an anisotropic photonic crystal

Cited by in corpus (14)

• Topological photonic crystals: physics, designs and applications
• Refractive index sensing with optical bound states in the continuum
• Bound states in the continuum in photonic structures
• Enhancing Goos-Hänchen shift based on magnetic dipole quasi-bound states in the continuum in all-dielectric metasurfaces
• Universal coupled theory for metamaterial Bound states in the continuum
• Optical bistability with bound states in the continuum in dielectric gratings
• Enhanced sensitivity of an all-dielectric refractive index sensor with optical bound state in the continuum
• One-dimensional quasi bound states in the continuum in the ω~k space for nonlinear optical applications
• Accidental and symmetry-protected bound states in the continuum in planar photonic-crystal structures, studied by the resonant-state expansion
• Extremely Narrow, Sharp-Peaked Resonances at the Edge of the Continuum
• Bound state in the continuum in an anisotropic photonic crystal supported by full-wave phase plate
• Realization of topological superlattices and the associated interface states in one-dimensional plasmonic crystals
• How many parameters do we need to obtain a BIC in symmetric and asymmetric structures?
• Topologically protected bound states in the continuum and strong phase resonances in integrated Gires-Tournois interferometer