摘要
动态调控是现代光学器件中必不可少的特性,在激光雷达系统、显示器件以及数码相机等设备中具有重要意义.与传统的体光学器件相比,动态超表面为实现小型化和集成化智能光学系统提供了一个极具吸引力的解决方案.相变材料具有高的折射率对比度和易于操控的特性,是设计动态超表面的理想材料.本文通过操控氧化钒的相变,在近红外区域设计实现了可调谐的超构透镜和可切换图像编码的超表面器件.通过控制氧化钒的相变,能够改变超透镜的聚焦强度,实现强度对比约为12倍的开关聚焦效果.此外,利用氧化钒的相变还设计实现了任意两个不同数字图案的可切换成像.本工作为实现动态成像和光学加密系统的可调谐超表面奠定了基础.
Dynamic properties play a vital role in modern optical devices,including light detection and ranging systems,display devices,and digital cameras.Active metasurfaces provide an attractive scheme for the miniaturization and integration of dynamic optical systems compared with traditional bulk optical devices.Phase transition materials are great candidates for the design of active metasurfaces due to their high contrast refractive index and simple control characteristics.Here,we present a tunable metalens and switchable image coding metasurface in the near-infrared region through the control of the phase transition of vanadium oxide.By adjusting the phase transition of vanadium oxide,the focal intensity of the metalens is changed,and a switching effect with an intensity contrast of~12 times is demonstrated.In addition,the switchable imaging of two different numbers has been achieved in two different phase states.This work provides potential opportunities to realize active metasurfaces for imaging and encryption systems.
作者
李月
谢建良
邓龙江
彭波
Yue Li;Jianliang Xie;Longjiang Deng;Bo Peng(National Engineering Research Center of Electromagnetic Radiation Control Materials,University of Electronic Science and Technology of China,Chengdu 611731,China;Key Laboratory of Multi Spectral Absorbing Materials and Structures of Ministry of Education,University of Electronic Science and Technology of China,Chengdu 611731,China)
基金
financially supported by the National Natural Science Foundation of China(51872039 and 52021001)
the Science and Technology Program of Sichuan(M112018JY0025)。
