论文标题
具有独立于极化的自适应纳米 - 安南的金属镜
Metalenses with polarization-independent adaptive nano-antennas
论文作者
论文摘要
近年来，Metalens Research取得了重大进步。这些进步依赖于在常规阵列中安排元原子的简单设计原理来创建任意阶段和极化曲线。不幸的是，在偏转效率降低的高挠度角度的高偏转角度的概念达到了极限。使用具有多个元素的纳米 - 安妮纳斯，可以提高效率，但是它们的极化敏感性阻碍了它们在金属中的应用。在这里，我们表明，通过设计对偏振敏感的二聚体纳米 - 安南群岛并放弃了相同间隔的单位细胞的原理，可以证明可以证明具有43％的非极化超高数值孔径（NA = 1.48）油浸入式操作。这代表了在可见波长下其他独立于极化的设计的显着改善。我们还使用这种单层金属剂来替换常规的物镜镜头，并演示了在532 nm工作波长下为300 nm的光栅的共聚焦扫描显微镜成像。总体而言，我们的结果在实验上展示了一种新颖的设计概念，可以进一步改善金属性能。
Metalens research has made major advances in recent years. These advances rely on the simple design principle of arranging meta-atoms in regular arrays to create an arbitrary phase and polarization profile. Unfortunately, the concept of equally spaced meta-atoms reaches its limit for high deflection angles where the deflection efficiency decreases. The efficiency can be increased using nano-antennas with multiple elements, but their polarization sensitivity hinders their application in metalenses. Here, we show that by designing polarization-insensitive dimer nano-antennas and abandoning the principle of equally spaced unit cells, polarization-independent ultrahigh numerical aperture (NA=1.48) oil-immersion operation with an efficiency of 43% can be demonstrated. This represents a significant improvement on other polarization-independent designs at visible wavelength. We also use this single layer metalens to replace a conventional objective lens and demonstrate the confocal scanning microscopic imaging of a grating with a period of 300 nm at 532 nm operating wavelength. Overall, our results experimentally demonstrate a novel design concept that further improves metalens performance.
