Plasmonic color generation utilizing ultrathin metasurfaces as well as metallic nanoparticles holds a great promise for a wide range of applications including color displays, data storage, and information encryption due to its high spatial resolution and mechanical/chemical stability. Most of the recently demonstrated systems generate static colors; however, more advanced applications such as data storage require fast and flexible means to tune the plasmonic colors, while keeping them vibrant and stable. Here, a surface‐relief aluminum metasurface that reflects polarization‐tunable plasmonic colors is designed and experimentally demonstrated. Excitation of localized surface plasmons encodes discrete combinations of the incident and reflected polarized light into diverse colors. A single storage unit, namely a nanopixel, stores multiple‐bit information in the orientation of its constituent nanoantennae, which is conveniently retrived by inspecting the reflected color sequence with two linear polarizers. Owing to the broad color variability and high spatial resolution of the metasurface, the proposed encoding approach holds a strong promise for rapid parallel readout and encryption of high‐density optical data. The method also enables robust generation of dynamic kaleidoscopic images without the “cross‐talk” effect. The approach opens up a new route for advanced dynamic steganography, high‐density parallel‐access optical data storage, and optical information encryption.

中文翻译：

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启用等速色彩的光学隐秘术，数据存储和加密

利用超薄超颖表面以及金属纳米粒子产生的等离子彩电因其高的空间分辨率和机械/化学稳定性而在包括彩色显示，数据存储和信息加密在内的广泛应用中具有广阔的前景。最近展示的大多数系统都会产生静态颜色。但是，诸如数据存储之类的更高级的应用程序需要快速灵活的方法来调整等离激元颜色，同时保持它们的活力和稳定性。在这里，设计并通过实验演示了一种表面起伏的铝超表面，该表面反射了偏振可调的等离激元颜色。激发局部表面等离子体激元可将入射和反射偏振光的离散组合编码为多种颜色。单个存储单元，即纳米像素，在其组成的纳米天线的方向上存储多位信息，可以方便地通过使用两个线性偏振器检查反射的颜色序列来检索该信息。由于超颖表面的宽泛的颜色可变性和高空间分辨率，所提出的编码方法对快速并行读出和加密高密度光学数据具有很大的希望。该方法还可以可靠地生成动态万花筒图像，而不会产生“串扰”效应。该方法为高级动态隐写技术，高密度并行访问光学数据存储和光学信息加密开辟了一条新途径。由于超表面的宽泛的颜色可变性和高空间分辨率，所提出的编码方法对快速并行读出和加密高密度光学数据具有很大的希望。该方法还可以可靠地生成动态万花筒图像，而不会产生“串扰”效应。该方法为高级动态隐写技术，高密度并行访问光学数据存储和光学信息加密开辟了一条新途径。由于超表面的宽泛的颜色可变性和高空间分辨率，所提出的编码方法对快速并行读出和加密高密度光学数据具有很大的希望。该方法还可以可靠地生成动态万花筒图像，而不会产生“串扰”效应。该方法为高级动态隐写技术，高密度并行访问光学数据存储和光学信息加密开辟了一条新途径。