Assembling Color on the Nanoscale: Multichromatic Switchable Pixels from Plasmonic Atoms and Molecules.
Assembling Color on the Nanoscale: Multichromatic Switchable Pixels from Plasmonic Atoms and Molecules.
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DOI：
10.1002/adma.201506179
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发表时间：
2016-05
期刊：
影响因子：
--
通讯作者：
Reinhard BM
中科院分区：
文献类型：
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作者：
Chen T;Reinhard BM
由于其大的光学截面和独特的光稳定性，等离子体纳米结构是下一代图像传感器和色彩检测或发射器件的极具吸引力的构建块，并且大大减少了占地面积。等离子体纳米结构、阵列和亚表面提供了编码复杂颜色和偏振图案的能力。后者在信息存储和密码应用中特别相关，以生成具有比传统全息技术可能的小得多的特征大小(并因此具有更高的数据密度)的安全标签或隐写术。要实现这些等离子体激元技术的全部潜力，就需要有能力产生能够编码多种颜色和偏振特性的“像素”。然而，通过自上而下图案化产生等离子体彩色像素的传统方法在成分和结构变化方面受到固有的限制。在此，我们介绍了一种顺序定向自组装方法，该方法有助于利用胶体等离子体纳米粒子(原子)及其组件(分子)的强烈的材料和形状依赖性来在电磁光谱的整个可见范围内产生可切换的颜色和极化图案。不同材料、形状和大小的纳米粒子通过单一图案化步骤后的顺序定向自组装，被整合到确定形状和位置的等离子体原子和分子中。证明了在电磁光谱的可见光范围内发射颜色的合理调谐和可切换的偏振特性。自组装等离子体像素提供可调、稳定和可切换的光学响应。
Due to their large optical cross sections and unique photostability, plasmonic nanostructures are attractive building blocks for next generation image sensors and color detecting or emitting devices with significantly decreased footprints. Plasmonic nanostructures, arrays and metasurfaces provide the ability to encode complex color and polarization patterns. The latter is of particular relevance in information storage and cryptographic applications to generate security tags or steganography with much smaller feature sizes (and thus higher data density) than is possible with conventional holographic techniques. The realization of the full potential of these plasmonic technologies requires the ability to generate “pixels” that can encode a broad range of colors and polarization properties. The conventional approach of generating plasmonic color pixels through top-down patterning is, however, intrinsically limited in compositional and structural variety. We introduce herein a sequential directed self-assembly approach that facilitates the utilization of the strong material- and shape-dependence of colloidal plasmonic nanoparticles (“atoms”) and their assemblies (“molecules”) to generate switchable color and polarization patterns across the entire visible range of the electromagnetic spectrum. Nanoparticles of different materials, shapes, and sizes are integrated into plasmonic atoms and molecules of defined shape and location through sequential directed self-assembly following a single patterning step. A rational tuning of the emitted color across the visible range of the electromagnetic spectrum and switchable polarization properties are demonstrated. Self-assembled plasmonic pixels provide tunable, stable, and switchable optical responses.