Engineering bound states in the continuum in metaphotonics

Abstract

Optical resonators confine light for a long but yet finite time due to unavoidable radiation. The concept of bound states in the continuum allows to reduce dramatically radiation from optical resonators due to interference and strong coupling akin exotic electronic waves introduced in quantum mechanics a century ago. This talk will summarize the recent progress in the physics and applications of bound states in the continuum (BICs) in metaphotonics. In particular, we aim to present the experimental observation of the quasi-BIC modes (also termed “supercavity modes”) in subwavelength high-index dielectric resonators in both radiofrequency and optics ranges. The supercavity mode manifests itself clearly via characteristic peculiarities of the Fano resonance and radiation patterns. We will also review the properties of other types of quasi-BIC modes such as those in extended structures and discuss their applications in nonlinear optics and ultrafast optical switching.