Actively Tunable Metalens Array Based on Patterned Phase Change Materials
Actively Tunable Metalens Array Based on Patterned Phase Change Materials
复制标题
基于图案化相变材料的主动可调谐超透镜阵列
DOI：
10.3390/app9224927
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发表时间：
2019-11-02
影响因子：
2.7
通讯作者：
Xu, Bing
中科院分区：
文献类型：
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作者：
Bai, Wei;Yang, Ping;Xu, Bing
近年来，由于金属透镜具有比传统透镜小得多、与纳米器件兼容等优点，其在许多领域的应用得到了广泛的研究。虽然金属透镜具有优异的光学性能，但在某些场合，如用于自适应光学的波前检测和用于大面积应用的显示，它仍然不够。使用金属透镜阵列是解决这些问题的理想解决方案。遗憾的是，普通的金属透镜阵列一旦制成就不能调整，这限制了它的应用范围。在本文中，我们首次通过合理地布置图案化相变材料Ge2Sb2Te5(GST)，设计了一种主动可调的金属透镜阵列。对于波长为4.6μm的金属透镜阵列，它在4.5~5.2μm的范围内具有良好的宽带性能。另一方面，通过调节金属透镜阵列的位相状态，可以控制金属透镜阵列的聚焦和显示，起到开关的作用。此外，当金属透镜阵列具有足够的二次单位单元时，可以获得利用图案化焦点构建的任何图形。所提出的金属透镜在自适应光学和动态显示领域具有潜在的应用价值。
Recently, the metalens has been investigated for its application in many fields due to its advantages of being much smaller than a conventional lens and is compatible with nano-devices. Although metalenses have extraordinary optical performance, it is still not enough in some occasions such as wavefront detection for adaptive optics and display for large area applications. Using a metalens array is an ideal solution to solve these problems. Unfortunately, the common metalens array cannot be adjusted once it is fabricated, which limits its range of application. In this article, we designed an actively tunable metalens array for the first time by arranging the patterned phase change material Ge2Sb2Te5 (GST) appropriately. For the metalens array designed at the wavelength of 4.6 μm, it had excellent broadband performance in the range from 4.5 μm to 5.2 μm. On the other hand, by tuning the phase state of GST, the focus and display of the metalens array can be controlled, acting as switching on or off. Furthermore, any graphics constructed with patterned focal spots can be achieved when the metalens array has sufficient secondary unit cells. The proposed metalens may have potential application value in the adaptive optics and dynamic display field.