Barelli Matteo, Mazzanti Andrea, Giordano Maria Caterina, Della Valle Giuseppe, Buatier de Mongeot Francesco
Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, I-16146 Genova, Italy.
Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci 32, I-20133 Milano, Italy.
Nano Lett. 2020 Jun 10;20(6):4121-4128. doi: 10.1021/acs.nanolett.9b05276. Epub 2020 May 21.
Bidirectional nanoantennas are of key relevance for advanced functionalities to be implemented at the nanoscale and, in particular, for color routing in an ultracompact flat-optics configuration. Here we demonstrate a novel approach avoiding complex collective geometries and/or restrictive morphological parameters based on cross-polarized detuned plasmonic nanoantennas in a uniaxial (quasi-1D) bimetallic configuration. The nanofabrication of such a flat-optics system is controlled over a large area (cm) by a novel self-organized technique exploiting ion-induced nanoscale wrinkling instability on glass templates to engineer tilted bimetallic nanostrip dimers. These nanoantennas feature broadband color routing with superior light scattering directivity figures, which are well described by numerical simulations and turn out to be competitive with the response of lithographic nanoantennas. These results demonstrate that our large-area self-organized metasurfaces can be implemented in real-world applications of flat-optics color routing from telecom photonics to optical nanosensing.
双向纳米天线对于在纳米尺度上实现先进功能至关重要，特别是对于超紧凑平面光学配置中的颜色路由。在这里，我们展示了一种新颖的方法，该方法基于单轴（准一维）双金属配置中的交叉极化失谐等离子体纳米天线，避免了复杂的集体几何形状和/或限制性形态参数。这种平面光学系统的纳米制造通过一种新颖的自组织技术在大面积（厘米）上进行控制，该技术利用离子诱导的玻璃模板上的纳米级皱纹不稳定性来设计倾斜的双金属纳米带二聚体。这些纳米天线具有宽带颜色路由，具有优异的光散射方向性系数，数值模拟很好地描述了这些系数，并且结果表明它们与光刻纳米天线的响应具有竞争力。这些结果表明，我们的大面积自组织超表面可以应用于从电信光子学到光学纳米传感的平面光学颜色路由的实际应用中。
