Hyperbolic metamaterials: From dispersion manipulation to applications

Manipulating the properties of the isofrequency contours (IFCs) of materials provides a powerful means of controlling the interaction between light and matter. Hyperbolic metamaterials (HMMs), an important class of artificial anisotropic materials with hyperbolic IFCs, have been intensively investigated. Because of their open dispersion curves, HMMs support propagating high-k modes and possess an enhanced photonic density of states. As a result, HMMs can be utilized to realize hyperlenses breaking the diffraction limit, metacavity lasers with subwavelength scale, high-sensitivity sensors, long-range energy transfer, and so on. Aimed at those who are about to enter this burgeoning and rapidly developing research field, this tutorial article not only introduces the basic physical properties of HMMs but also discusses dispersion manipulation in HMMs and HMM-based structures such as hypercrystals. Both theoretical methods and experimental platforms are detailed. Finally, some potential applications associated with hyperbolic dispersion are introduced.