Photonic edge states provide a novel platform to control and enhance light–matter interactions. Recently, it becomes increasing popular to generate such localized states using the bulk-edge correspondence of topological photonic crystals. While the topological approach is elegant, the design and fabrication of these complex photonic topological crystals is tedious. Here, we report a simple and effective strategy to construct and steer photonic edge state in a plasmonic meta-array, which just requires a small number of plasmonic nanoparticles to form a simple lattice. To demonstrate the idea, different lattice configurations, including square, triangular, and honeycomb lattices of meta-arrays, are fabricated and measured by using an ultrahigh spatial resolution photoemission electron microscopy. The properties of edge states depend on the geometric details such as the row and column number of the lattice, as well as the gap distance between the particles. Moreover, numerical simulations show that the excited edge states can be used for the generation of the quantum entanglement. This work not only provides a new platform for the study of nanoscale photonic devices, but also open a new way for the fundamental study of nanophotonics based on edge states.

中文翻译：

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等离子体元阵列中的边缘状态

光子边缘态提供了一个新的平台来控制和增强光与物质的相互作用。最近，使用拓扑光子晶体的体边缘对应来生成这种局部状态变得越来越流行。虽然拓扑方法很优雅，但这些复杂光子拓扑晶体的设计和制造却很乏味。在这里，我们报告了一种简单有效的策略来构建和控制等离子体元阵列中的光子边缘状态，该策略只需要少量等离子体纳米颗粒即可形成简单的晶格。为了证明这一想法，使用超高空间分辨率光电发射电子显微镜制造和测量了不同的晶格配置，包括元阵列的方形、三角形和蜂窝晶格。边缘状态的性质取决于几何细节，例如晶格的行数和列数，以及粒子之间的间隙距离。此外，数值模拟表明激发边缘态可用于产生量子纠缠。该工作不仅为纳米光子器件的研究提供了新平台，也为基于边缘态的纳米光子学基础研究开辟了新途径。