摘要
Traditional optical components are usually designed for a single functionality and narrow operation band,leading to the limited practical applications.To date,it is still quite challenging to efficiently achieve multifunctional performances within broadband operating bandwidth via a single planar optical element.Here,a broadband high-efficiency polarization-multiplexing method based on a geometric phase polymerized liquid crystal metasurface is proposed to yield the polarization-switchable functionalities in the visible.As proofs of the concept,two broadband high-efficiency polymerized liquid crystal metalenses are designed to obtain the spin-controlled behavior from diffraction-limited focusing to sub-diffraction focusing or focusing vortex beams.The experimental results within a broadband range indicate the stable and excellent optical performance of the planar liquid crystal metalenses.In addition,low-cost polymerized liquid crystal metasurfaces possess unique superiority in large-scale patterning due to the straightforward processing technique rather than the point-by-point nanopatterning method with high cost and low throughput.The high-efficiency liquid crystal metasurfaces also have unrivalled advantages benefiting from the characteristic with low waveguide absorption.The proposed strategy paves the way toward multifunctional and high-integrity optical systems,showing great potential in mobile devices,optical imaging,robotics,chiral materials,and optical interconnections.
基金
National Key Research and Development Program of China(SQ2021YFA1400121)
National Natural Science Foundation of China(61875253,61975210,U20A20217)
Youth Innovation Promotion Association of the Chinese Academy of Sciences(2019371)。