Microcavity-assisted multi-resonant metasurfaces enabling versatile wavefront engineering

Metasurfaces have exhibited exceptional proficiency in precisely modulating light properties within narrow wavelength spectra. However, there is a growing demand for multi-resonant metasurfaces capable of wavefront engineering across broad spectral ranges. In this study, we introduce a microcavity-assisted multi-resonant metasurface platform that integrates subwavelength meta-atoms with a specially designed distributed Bragg reflector (DBR) substrate. This platform enables the simultaneous excitation of various resonant modes within the metasurface, resulting in multiple high-Q resonances spanning from the visible to the near-infrared (NIR) regions. The developed metasurface generates up to 15 high-Q resonant peaks across the visible-NIR spectrum, achieving a maximum efficiency of 81% (70.7%) in simulation (experiment) with an average efficiency of 76.6% (54.5%) and a standard deviation of 4.1% (11.1%). Additionally, we demonstrate the versatility of the multi-resonant metasurface in amplitude, phase, and wavefront modulations at peak wavelengths. By integrating structural color printing and vectorial holographic imaging, our proposed metasurface platform shows potential for applications in optical displays and encryption. This work paves the way for the development of next-generation multi-resonant metasurfaces with broad-ranging applications in photonics and beyond.