Photonic Bound States in the Continuum: From Basics to Applications

The introduction of bound states in the continuum (BICs) to photonics has revolutionized the way cavity design and light-matter interactions are thought about in general. BICs can have very high quality factors, even in open structures where access to radiation is permissible. Now, BICs found applications in a large class of areas, including nonlinear enhancement, coherent light generation, sensors, filters, integrated circuits, and many others. In this review, the different types of BICs in photonic systems, as well as their physics and formation mechanisms are briefly overviewed. The rest of the review focuses on the current and emerging applications of photonic BICs and their role in shaping the interaction of light and matter.