Floris Francesco, Fornasari Lucia, Marini Andrea, Bellani Vittorio, Banfi Francesco, Roddaro Stefano, Ercolani Daniele, Rocci Mirko, Beltram Fabio, Cecchini Marco, Sorba Lucia, Rossella Francesco
Dipartimento di Fisica, Università di Pavia, via Bassi 6, 27100 Pavia, Italy.
ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain.
Nanomaterials (Basel). 2017 Nov 21;7(11):400. doi: 10.3390/nano7110400.
Subwavelength nanostructured surfaces are realized with self-assembled vertically-aligned InAs nanowires, and their functionalities as optical reflectors are investigated. In our system, polarization-resolved specular reflectance displays strong modulations as a function of incident photon energy and angle. An effective-medium model allows one to rationalize the experimental findings in the long wavelength regime, whereas numerical simulations fully reproduce the experimental outcomes in the entire frequency range. The impact of the refractive index of the medium surrounding the nanostructure assembly on the reflectance was estimated. In view of the present results, sensing schemes compatible with microfluidic technologies and routes to innovative nanowire-based optical elements are discussed.
利用自组装垂直排列的 InAs 纳米线实现了亚波长纳米结构表面，并研究了其作为光学反射器的功能。在我们的系统中，偏振分辨镜面反射率随入射光子能量和角度呈现出强烈的调制。有效介质模型有助于在长波长范围内合理解释实验结果，而数值模拟则能在整个频率范围内完全重现实验结果。估计了纳米结构组件周围介质的折射率对反射率的影响。鉴于目前的结果，讨论了与微流体技术兼容的传感方案以及基于纳米线的创新光学元件的发展途径。
