Tunable optical properties via plasmonic metaphotonics with random and regular nanostructures

Metamaterials are artificial materials exhibiting optical properties unattainable in nature. Among them, plasmonic metamaterials based on metallic nanostructures enable flexible control of optical properties in the visible spectrum. We have developed a cost-effective and scalable approach to plasmonic metamaterials using random nanostructures, eliminating the need for conventional top-down nanofabrication. This allows full-color tunability of resonance wavelengths, facilitating applications in full-color light sources and displays, while significantly improving the resonance quality factor for next-generation optical devices such as nanolasers and high-efficiency, high-speed LEDs. Additionally, aluminum-based nanosphere structures extend localized surface plasmon resonance into the deep-UV regime, advancing deep-UV LED technology for water sterilization and photolithography. Beyond traditional plasmonics and metamaterials, our research positions these developments within a broader concept of metaphotonics, incorporating evanescent near-field light, optical localization effects, and quantum interactions, expanding their impact on sensing, imaging, and meta-optics.