Wang Dapeng, Hwang Yongsop, Dai Yanmeng, Si Guangyuan, Wei Shibiao, Choi Duk-Yong, Gómez Daniel E, Mitchell Arnan, Lin Jiao, Yuan Xiaocong
Nanophotonics Research Centre, Shenzhen Key Laboratory of Micro-Scale Optical Information Technology, Shenzhen University, Shenzhen, 518060, China.
School of Engineering, RMIT University, Melbourne, Victoria, 3000, Australia.
Small. 2019 May;15(20):e1900483. doi: 10.1002/smll.201900483. Epub 2019 Apr 15.
Simultaneous broadband and high efficiency merits of designer metasurfaces are currently attracting widespread attention in the field of nanophotonics. However, contemporary metasurfaces rarely achieve both advantages simultaneously. For the category of transmissive metadevices, plasmonic or conventional dielectric metasurfaces are viable for either broadband operation with relatively low efficiency or high efficiency at only a selection of wavelengths. To overcome this limitation, dielectric nanoarcs are proposed as a means to accomplish two advantages. Continuous nanoarcs support different electromagnetic resonant modes at localized areas for generating phase retardation. Meanwhile, the geometric nature of nanoarc curvature endows the nanoarcs with full phase coverage of 0-2π due to the Pancharatnam-Berry phase principle. Experimentally incorporated with the chiral-detour phase principle, a few compelling functionalities are demonstrated, such as chiral beamsplitting, broadband holography, and helicity-selective holography. The continuous nanoarc metasurfaces prevail over plasmonic or dielectric discretized building block strategies and the findings lead to novel designs of spin-controllable metadevices.
设计超表面同时具备的宽带和高效特性目前在纳米光子学领域引起了广泛关注。然而，当代超表面很少能同时实现这两个优点。对于透射型超器件类别，等离子体或传统介电超表面对于以相对较低效率进行宽带操作或仅在选定波长下实现高效率来说是可行的。为了克服这一限制，人们提出了介电纳米弧作为实现这两个优点的一种手段。连续纳米弧在局部区域支持不同的电磁共振模式以产生相位延迟。同时，由于潘查拉特纳姆 - 贝里相位原理，纳米弧曲率的几何性质赋予纳米弧0 - 2π的全相位覆盖。通过实验结合手性迂回相位原理，展示了一些引人注目的功能，如手性光束分裂、宽带全息术和螺旋度选择性全息术。连续纳米弧超表面优于等离子体或介电离散化构建块策略，这些发现促成了自旋可控超器件的新颖设计。
