Realization of Artificially Controlled Dispersion in Hyperbolic Metamaterials

Hyperbolic metamaterials, strategically engineered subwavelength structures, exhibit highly anisotropic electromagnetic properties that give rise to hyperbolic dispersion relations. This unique characteristic enables the support and manipulation of high‐spatial‐frequency modes that are inaccessible in conventional materials. In this review, the underlying principles and design strategies are presented for realizing hyperbolic metamaterials. An overview of their operation mechanisms, fabrication methods, and representative applications is provided. Furthermore, this review highlights how these structures enable unprecedented functionalities such as super‐resolution imaging, scattering and absorption mode engineering, ultrasensitive sensing, and broadband absorption, which are rarely achievable with natural materials. In addition, they open pathways to further advancements, including all‐optical switching, nonlinear optics, and magneto‐optical sensing, thereby emphasizing their potential for next‐generation photonics technologies.