Guo Jingjing, Tu Yan, Yang Lanlan, Zhang Ruiwen, Wang Lili, Wang Baoping
Joint International Research Laboratory of Information Display and Visualization, School of Electronic Science and Engineering, Southeast University, Nanjing, 210096, China.
Sci Rep. 2017 Oct 26;7(1):14078. doi: 10.1038/s41598-017-14583-7.
In this paper, an electrically tunable metasuface is designed for visible regime. The device mainly consists of a V-shaped metallic metasurface, an ITO film, an electro-optic (EO) dielectric and a metal layer fabricated on a silica substrate. A continuous electrical modulation of resonant wavelength has been theoretically demonstrated in the visible range from 555 nm to 640 nm by changing the voltage applied on the EO dielectric from -20 V to 20 V. During the modulation, the steering angle also changes with the selective color. The peak cross-polarized reflectivity is higher than 48% and the bandwidth is narrower than 60 nm. The resonant wavelength shift can be explained by that the refractive index variation of the EO material induces resonance condition changes of the gap surface plasmon (GSP). The results provide a novel design solution for active plasmonic devices, especially for dynamic metadevices.
本文设计了一种用于可见光波段的电调谐超表面。该器件主要由一个V形金属超表面、一层ITO薄膜、一种电光（EO）电介质和一个制备在二氧化硅衬底上的金属层组成。通过将施加在EO电介质上的电压从-20 V改变到20 V，理论上证明了在555 nm至640 nm的可见光范围内谐振波长的连续电调制。在调制过程中，转向角也随所选颜色而变化。峰值交叉极化反射率高于48%，带宽窄于60 nm。谐振波长的移动可以解释为EO材料的折射率变化引起了间隙表面等离子体激元（GSP）的共振条件变化。这些结果为有源等离子体器件，特别是动态超器件提供了一种新颖的设计方案。
