Yang Zhenyu, Yu Dahai, Zhang Huiping, Yu Anqi, Guo Xuguang, Ren Yuxiang, Zang Xiaofei, Balakin Alexei V, Shkurinov Alexander P
Shanghai Key Lab of Modern Optical System, Terahertz Spectrum and Imaging Technology Cooperative Innovation Center, Terahertz Technology Innovation Research Institute, University of Shanghai for Science and Technology, 516 Jungong Road, Shanghai 200093, China.
Focused Photonics (Hangzhou) Inc., No: 760, Bin'an Road, Binjiang District, Hangzhou 310052, China.
Nanomaterials (Basel). 2021 Jul 18;11(7):1851. doi: 10.3390/nano11071851.
In this work, we propose a structure consisting of three metamaterial layers and a metallic grating layer to rotate the polarization of arbitrary linearly polarized incidence to the y-direction with high transmissivity by electrically tuning these metamaterials. The transfer matrix method together with a harmonic oscillator model is adopted to theoretically study the proposed structure. Numerical simulation based on the finite difference time-domain method is performed assuming that the metamaterial layers are constituted by graphene ribbon arrays. The calculation and simulation results show that the Drude absorption is responsible for the polarization rotation. Fermi level and scattering rate of graphene are important for the transmissivity. For a polarization rotation of around 90°, the thickness of either the upper or lower dielectric separations influences the transmission window. For a polarization rotation of around 45° and 135°, the lower dielectric separations decide the frequency of the transmission window, while the upper dielectric separations just slightly influence the transmissivity.
在这项工作中，我们提出了一种由三个超材料层和一个金属光栅层组成的结构，通过对这些超材料进行电调谐，将任意线偏振入射光的偏振旋转到y方向，并具有高透射率。采用传输矩阵法结合谐波振荡器模型对所提出的结构进行理论研究。假设超材料层由石墨烯带阵列构成，基于时域有限差分法进行了数值模拟。计算和模拟结果表明，德鲁德吸收是导致偏振旋转的原因。石墨烯的费米能级和散射率对透射率很重要。对于约90°的偏振旋转，上下介质间隔层的厚度会影响透射窗口。对于约45°和135°的偏振旋转，下部介质间隔层决定透射窗口的频率，而上部介质间隔层仅对透射率有轻微影响。
