Abstract Ultrathin Fresnel lens may revolutionize current optical imaging system, leading to thinner and lighter optoelectronic devices with a myriad of technical applications. To date, evaporated bulk metal films and top-down grown graphene represent viable material choices toward the design of ultrathin Fresnel lenses. Despite recent advances, it is still lack of a scalable fabrication strategy to achieve ultrathin lens with high focusing efficiency. Here, we report a new self-assembled metamaterials-based strategy to design ultrathin Fresnel lens using our recently reported plasmene nanosheets. With comparable thickness, our plasmene-based Fresnel lens offers a much better focusing efficiency than that based on continuous metallic films. This may be attributed to the dual Huygens’ effects from both slits and plasmene-constituent nanoparticle building blocks. Importantly, internal structural features of plasmene can be precisely tuned simply by adjusting sizes and shapes of its constituent building blocks, allowing for maximizing the focusing efficiency at a desired operating wavelength – a capability impossible to achieve with continuous metal films or graphene. Our plasmene-based strategy opens a new route to design tailor-made flat lens with finely tunable internal and overall structural properties, which offers new dimensionalities in controlling light-matter interactions for a myriad of technological applications.

中文翻译：

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基于等离子体纳米片的超薄菲涅尔透镜

摘要 超薄菲涅尔透镜可能会彻底改变当前的光学成像系统，导致更薄、更轻的光电器件具有无数的技术应用。迄今为止，蒸发的块状金属薄膜和自上而下生长的石墨烯代表了超薄菲涅耳透镜设计的可行材料选择。尽管最近取得了进展，但仍缺乏可扩展的制造策略来实现具有高聚焦效率的超薄透镜。在这里，我们报告了一种新的基于自组装超材料的策略，使用我们最近报道的等离子体纳米片设计超薄菲涅耳透镜。我们的基于等离子体的菲涅耳透镜具有相当的厚度，比基于连续金属薄膜的透镜具有更好的聚焦效率。这可能归因于来自狭缝和等离子体组成的纳米颗粒构建块的双重惠更斯效应。重要的是，等离子体的内部结构特征可以通过简单地调整其组成构件的尺寸和形状来精确调整，从而最大限度地提高所需工作波长下的聚焦效率——这是连续金属膜或石墨烯无法实现的能力。我们基于等离子体的策略开辟了一条新途径来设计具有精细可调内部和整体结构特性的定制平面透镜，这为无数技术应用提供了控制光-物质相互作用的新维度。允许在所需的工作波长下最大化聚焦效率——这是使用连续金属薄膜或石墨烯无法实现的能力。我们基于等离子体的策略开辟了一条新途径来设计具有精细可调内部和整体结构特性的定制平面透镜，这为无数技术应用提供了控制光-物质相互作用的新维度。允许在所需的工作波长下最大化聚焦效率——这是使用连续金属薄膜或石墨烯无法实现的能力。我们基于等离子体的策略开辟了一条新途径来设计具有精细可调内部和整体结构特性的定制平面透镜，这为无数技术应用提供了控制光-物质相互作用的新维度。