Reliable and repeatable tunability gives functional diversity for reconfigurable plasmonics devices, while reversible and large mechanical deformation enabled by soft materials provides a new way for the global or partial regulation of metadevices. Here, we demonstrate a soft metasurface with an out-of-plane design for tuning the energy of surface plasmon polaritons (SPPs) bloch wave using theory, simulation, and experiments. Our metasurface is composed of two-layered gold nanoribbon arrays (2GNRs) on a soft substrate. The out-of-plane coupling mechanism is systematically analyzed in terms of separation height effect. Moreover, by harnessing mechanical deformation, continuously tunable plasmonic resonance has been achieved in the visible and near-infrared ranges. We further studied the angle-dependent reflection spectra of our metastructure. Compared with its planar counterpart, our soft and two-layered metastructure exhibits diverse tunability and significant field enhancement by out-of-plane interactions. Our approach in designing soft metasurface with out-of-plane structures can be extended to more-complex photonic devices and finds prominent applications such as biosensing, high-density plasmonic circuits, surface-enhanced luminescence, and surface-enhanced Raman scattering.

中文翻译：

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平面外设计的可调谐表面等离子极化的软超表面

可靠且可重复的可调性为可重配置的等离子设备提供了功能多样性，而软材料实现的可逆且较大的机械变形为元设备的全局或部分调节提供了新途径。在这里，我们演示了一种具有平面外设计的软超表面，用于使用理论，模拟和实验来调整表面等离激元极化子（SPPs）bloch波的能量。我们的超颖表面由在柔软基底上的两层金纳米带阵列（2GNR）组成。从分离高度效应的角度系统地分析了面外耦合机制。此外，通过利用机械变形，在可见光和近红外范围内实现了连续可调的等离子体共振。我们进一步研究了我们的元结构的角度依赖性反射光谱。与平面结构相比，我们的软结构和两层结构通过平面外相互作用显示出多种可调性和显着的场增强效果。我们使用平面外结构设计软超表面的方法可以扩展到更复杂的光子设备，并找到了诸如生物传感，高密度等离子体电路，表面增强的发光和表面增强的拉曼散射等重要应用。