Singular states of resonant nanophotonic lattices

Abstract Fundamental effects in nanophotonic resonance systems focused on singular states and their properties are presented. Strongly related to lattice geometry material composition, there appear resonant bright channels non-resonant dark the spectra. The state corresponds high reflectivity guided-mode (GMR) whereas channel represents a bound continuum (BIC). Even simple systems, with tunable bandwidth as isolated spectral lines that widely separated from other features. Under moderate modulation, ensues leaky-band metamorphosis, merging modal bands resulting offset reflective BICs along transmissive within high-reflectance wideband. Rytov-type effective medium theory (EMT) is shown be powerful means describe, formulate, understand collective GMR/BIC fundamentals photonic systems. Particularly, discarded Rytov analytical solution for asymmetric fields here predict BIC essentially exactly considerable modulation levels. propagation constant of an equivalent EMT homogeneous film provides quantitative evaluation eminent, oft-cited embedded eigenvalue. work concludes experimental verification key effects.