Chen Mingming, Yang Xue-Xia
School of Communication and Information Engineering, Shanghai University, Shanghai, China.
Key Laboratory of Specialty Fiber Optics and Optical Access Networks, School of Communication and Information Engineering, Shanghai University, Shanghai, China.
Phys Chem Chem Phys. 2023 Aug 16;25(32):21547-21553. doi: 10.1039/d3cp03072e.
A high-transmission and large group delay terahertz triple-band electromagnetically induced transparency (EIT) effect is obtained in a metal-perovskite hybrid metasurface, which consists of a cross metal (CM), a pair of square metal frames (SMFs), and a pair of square split rings (SSRs). The results reveal that the transmission amplitudes of three transparent windows are 0.83, 0.9, and 0.89. The maximum values of group delays at three transparent windows are 7.64 ps, 4.07 ps, and 4.27 ps. The multipole scattering theory shows that the first and third transparent windows are created by the coupling between the electric dipole and toroidal dipole, and the second transparent window is created by the electric dipoles. The triple-band EIT effect can be dynamically controlled by adjusting the conductivity of perovskite while the modulation depths are 49.4%, 41%, and 31.5%. Moreover, the slow light effect can also be tunable by tuning the conductivity of perovskite while the modulation depths are 87.8%, 65.6%, and 68.4%. Our study puts forward a novel design concept for multi-band EIT effect and shows great prospects in the application of multi-band devices.
在一种金属 - 钙钛矿混合超表面中获得了高透射率和大群延迟的太赫兹三波段电磁诱导透明（EIT）效应，该超表面由一个十字形金属（CM）、一对方形金属框架（SMF）和一对方形裂环（SSR）组成。结果表明，三个透明窗口的透射幅度分别为0.83、0.9和0.89。三个透明窗口处的群延迟最大值分别为7.64 ps、4.07 ps和4.27 ps。多极散射理论表明，第一和第三个透明窗口是由电偶极子与环形偶极子之间的耦合产生的，而第二个透明窗口是由电偶极子产生的。通过调节钙钛矿的电导率可以动态控制三波段EIT效应，其调制深度分别为49.4%、41%和31.5%。此外，通过调节钙钛矿的电导率也可以使慢光效应可调，其调制深度分别为87.8%、65.6%和68.4%。我们的研究提出了一种用于多波段EIT效应的新颖设计概念，并在多波段器件的应用中显示出巨大的前景。
