China's Top Ten Advances in Optics: Research Progress on Optical Applications of Anomalous Deflection Metasurfaces (Invited)

Deflecting light waves is an important capability in the manipulation of optical fields and serves as a fundamental aspect in numerous optical applications. With the vigorous development of optical technology, there is an urgent need for optical devices that balance miniaturization and beam deflection ability. Metasurfaces, which are planar devices constructed by arranging sub-wavelength nano-structures with specific order, can redirect light waves towards non-specular directions due to the ability to modulate electromagnetic waves with arbitrary customization, offering the potential to play a significant role in practical applications. In this paper, we first introduce the physical mechanisms underlying the high-efficiency anomalous deflection metasurfaces, then provide a review and discussion of the applications of anomalous deflection metasurfaces and finally summarize potential challenges, offer a glimpse into the future development of anomalous deflection metasurfaces and their applications.