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Simultaneous realization of printing and holographic images has become an emerging and promising technology for optical storage and anti‐counterfeiting, which can significantly enhance the information capacity and security of an optical system. Herein, a non‐interleaved four‐channel metasurface based on opposite‐chirality‐coexisted meta‐atoms is proposed, which can simultaneously support four independent circular polarization (CP) information channels, including two near‐field printing channels and two far‐field holography channels. In addition, due to the chiral resonance properties, the operation frequencies of these four polarization channels can also be flexibly designed to simultaneously achieve polarization multiplexing and frequency multiplexing. As a proof of concept, two four‐channel metasurfaces, one of which works at a single frequency and the other works at two different frequencies, are designed and validated numerically and experimentally. It is shown in the results that two printing and two holographic images with different handedness can be stored at one frequency or two different frequencies through the flexible design of metasurface. This four‐channel metasurface provides a new avenue for the design of future photonic devices with highly integrated and multiple functionalities, and may have an advantage in diverse potential applications, such as advanced anti‐counterfeits, optical data storage, and image displays. [ABSTRACT FROM AUTHOR]

Simultaneous realization of printing and holographic images has become an emerging and promising technology for optical storage and anti‐counterfeiting, which can significantly enhance the information capacity and security of an optical system. Herein, a non‐interleaved four‐channel metasurface based on opposite‐chirality‐coexisted meta‐atoms is proposed, which can simultaneously support four independent circular polarization (CP) information channels, including two near‐field printing channels and two far‐field holography channels. In addition, due to the chiral resonance properties, the operation frequencies of these four polarization channels can also be flexibly designed to simultaneously achieve polarization multiplexing and frequency multiplexing. As a proof of concept, two four‐channel metasurfaces, one of which works at a single frequency and the other works at two different frequencies, are designed and validated numerically and experimentally. It is shown in the results that two printing and two holographic images with different handedness can be stored at one frequency or two different frequencies through the flexible design of metasurface. This four‐channel metasurface provides a new avenue for the design of future photonic devices with highly integrated and multiple functionalities, and may have an advantage in diverse potential applications, such as advanced anti‐counterfeits, optical data storage, and image displays.

By virtue of the extraordinary capability of manipulating the polarization state, amplitude and phase of electromagnetic fields, metasurfaces can be employed to display holographic or nanoprinting images with unprecedented spatial resolution. Bringing holography and nanoprinting together is an effective way toward information multiplexing. However, current approaches mostly utilize interleaving or stacking nanostructures with different functionalities to construct multiplexed metasurfaces, hence they are equivalent to a combination of several metasurfaces and the information capacity of each metasurface remains unchanged. Here, by combining intensity modulation governed by Malus's law with phase manipulation based on both geometric and propagation phases, a single‐cell‐designed metasurface for three‐channel image displays is proposed. The new design strategy can significantly improve the information capacity since the extra phase modulation originates from the orientation degeneracy and dimension variation of nanostructures rather than multilayer or interleaving design. Specifically, a three‐channel metasurface is experimentally demonstrated, which can simultaneously record a continuous grayscale nanoprinting image in the near field and project two independent holographic images in the far field. With the advantages of crosstalk‐free and ultracompactness, the proposed three‐channel metasurfaces can empower the design of multifunctional nano‐optical elements for applications in image displays, optical anticounterfeiting, optical storage and many other related fields. [ABSTRACT FROM AUTHOR]