Resonance effects in photonic crystals and metamaterials (100th anniversary of the Ioffe Institute)

We review experimental and theoretical studies of resonance effects in electromagnetic spectra of various photon„ic structures. We briefly present the history of research areas related to photonic crystals and metamaterials. Considered initially as two different classes of human-made objects, they are now more and more frequently analyzed from a common perspective. We focus on the phase transition between the photonic crystal and metamaterial, which is accompanied by the emergence of negative permeability in a purely dielectric 2D structure. The main mechanisms that drive the resonant processes related to extended (i.e., nonlocal) Bragg resonances in photonic crystals and local resonances on individual structural elements of metamaterials are considered. We discuss in detail the electromagnetic properties of weakly absorbing dielectric particles with a high refractive index that exhibit, in addition to electrical resonances, intensive magnetic Mie resonances. The importance of this area is determined by the vast amount of research that aims to create the elemental base of photonics.