Nonreciprocal Asymmetric Polarization Encryption by Layered Plasmonic Metasurfaces
Nonreciprocal Asymmetric Polarization Encryption by Layered Plasmonic Metasurfaces
复制标题
分层等离子体超表面的非互易不对称偏振加密
DOI：
10.1021/acs.nanolett.9b01298
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发表时间：
2019-06-01
期刊：
影响因子：
10.8
通讯作者：
Zentgraf, Thomas
中科院分区：
文献类型：
--
作者：
Frese, Daniel;Wei, Qunshuo;Zentgraf, Thomas
作为可以操纵光的相位和振幅的柔性光学器件，超表面将明显受益于定向光学特性。然而，由二维纳米颗粒阵列组成的单层超颖表面系统仅表现出垂直于表面的弱空间不对称性，因此具有大部分对称的透射特征。在这里，我们提出了一个元表面的设计原则，非互易偏振加密的全息图像。我们的方法是基于一个两层的等离子体元表面的设计，引入了局部不对称性，并产生一个双向的功能与全相位和振幅控制的透射光。编码全息图被设计成出现在特定的线性交叉偏振信道中，而它在反向传播方向上消失。因此，分层的超表面系统可以以具有全相位和幅度控制的非对称传输为特征，并且因此将纳米级光学器件中的设计自由度扩展到非对称信息处理和防伪应用的安全特征。
As flexible optical devices that can manipulate the phase and amplitude of light, metasurfaces would clearly benefit from directional optical properties. However, single layer metasurface systems consisting of two-dimensional nanoparticle arrays exhibit only a weak spatial asymmetry perpendicular to the surface and therefore have mostly symmetric transmission features. Here, we present a metasurface design principle for nonreciprocal polarization encryption of holographic images. Our approach is based on a two-layer plasmonic metasurface design that introduces a local asymmetry and generates a bidirectional functionality with full phase and amplitude control of the transmitted light. The encoded hologram is designed to appear in a particular linear cross-polarization channel, while it is disappearing in the reverse propagation direction. Hence, layered metasurface systems can feature asymmetric transmission with full phase and amplitude control and therefore expand the design freedom in nanoscale optical devices toward asymmetric information processing and security features for anticounterfeiting applications.