Dielectric-Based Metamaterials for Near-Perfect Light Absorption

The emergence of metamaterials and their continued prosperity have built a powerful working platform for accurately manipulating the behavior of electromagnetic waves, providing sufficient possibility for the realization of metamaterial absorbers with outstanding performance. However, metamaterial absorbers composed of metallic materials typically possess many unfavorable factors, such as non-adjustable absorption, easy oxidation, low-melting, and expensive preparation costs. The selection of dielectric materials provides excellent alternatives due to their remarkable properties, thus dielectric-based metamaterial absorbers (DBMAs) have attracted much attention. To promote breakthroughs in DBMAs and guide their future development, this work systematically and deeply reviews the recent research progress of DBMAs from four different but progressive aspects, including physical principles; classifications, material selections and tunable properties; preparation technologies; and functional applications. Five different types of theories and related physical mechanisms, such as Mie resonance, guided-mode resonance, and Anapole resonance, are briefly outlined to explain DBMAs having near-perfect absorption performance. Mainstream material selections, structure designs, and different types of tunable DBMAs are highlighted. Several widely utilized preparation methods for customizing DBMAs are given. Various practical applications of DBMAs in sensing, stealth technology, solar energy absorption, and electromagnetic interference suppression are reviewed. Finally, some key challenges and feasible solutions for DBMAs' future development are provided. This review provides an in-depth and systematic summary of the latest research progress in the dielectric-based metamaterial absorbers, focusing on four key but gradually progressive aspects, including 1) physical principles, 2) classifications, material selections, and tunable properties, 3) mainstream preparation strategies, and 4) functional applications, with the purpose of promoting breakthroughs in dielectric-based metamaterial absorbers and guiding their future development. image