Zhang Xu A, Chen Yi-An, Bagal Abhijeet, Chang Chih-Hao
Opt Lett. 2017 Oct 15;42(20):4123-4126. doi: 10.1364/OL.42.004123.
Low-index materials are key components in integrated photonics and can enhance index contrast and improve performance. Such materials can be constructed from porous materials, which generally lack mechanical strength and are difficult to integrate. Here we demonstrate enhanced total internal reflection (TIR) induced by integrating robust nanolattice materials with periodic architectures between high-index media. The transmission measurement from the multilayer stack illustrates a cutoff at about a 60° incidence angle, indicating an enhanced light trapping effect through TIR. Light propagation in the nanolattice material is simulated using rigorous coupled-wave analysis and transfer matrix methods, which agrees well with experimental data. The demonstration of the TIR effect in this Letter serves as a first step towards the realization of multilayer devices with nanolattice materials as robust low-index components. These nanolattice materials can find applications in integrated photonics, antireflection coatings, photonic crystals, and low-k dielectric.
低折射率材料是集成光子学中的关键组件，可增强折射率对比度并提高性能。此类材料可由多孔材料构建而成，而多孔材料通常缺乏机械强度且难以集成。在此，我们展示了通过将具有周期性结构的坚固纳米晶格材料集成到高折射率介质之间所诱导的增强型全内反射（TIR）。多层堆叠结构的透射测量表明，在约60°入射角处存在截止现象，这表明通过全内反射实现了增强的光捕获效应。使用严格耦合波分析和传输矩阵方法对纳米晶格材料中的光传播进行了模拟，模拟结果与实验数据吻合良好。本信函中全内反射效应的演示是迈向以纳米晶格材料作为坚固低折射率组件实现多层器件的第一步。这些纳米晶格材料可应用于集成光子学、抗反射涂层、光子晶体和低介电常数电介质。
