Ren Bin, Feng Yuxin, Tang Shuai, Wang Li, Jiang Huan, Jiang Yongyuan
Opt Express. 2021 May 24;29(11):17258-17268. doi: 10.1364/OE.426645.
Polarization modulation and multichannel beam generation are crucial in multichannel communication and high-resolution imaging at THz frequency. In this work, we present a polarization-reprogrammable coding metasurface composed of VO/Au composite concentric rings (CCRs). Owing to the phase-change property of VO, the CCR is designed as a digital coding element for the polarization conversion. When VO remains insulator state at room temperature, the y-polarized incident wave is transformed into x-polarized wave, which can be regarded as digital state 0. When VO converts into metal state at critical temperature (68 °C), the polarization of reflected wave stays unchanged, corresponding to digital state 1. Any desired linear polarization state of reflected beam is achieved by taking advantage of different coding sequences in a programmable manner. Furthermore, by combining phase gradient with polarization coding states, we propose an anisotropic programmable metasurface to control the multi-channel reflected beams dynamically. By arranging distinct coding sequences, we show that the EM reflected beams can be manipulated flexibly. The proposed programmable metasurface paves new ways towards THz polarization manipulation, signal detection and information communication.
偏振调制和多通道光束生成在太赫兹频率的多通道通信和高分辨率成像中至关重要。在这项工作中，我们展示了一种由VO/Au复合同心环（CCR）组成的可重新编程偏振编码超表面。由于VO的相变特性，CCR被设计为用于偏振转换的数字编码元件。当VO在室温下保持绝缘状态时，y偏振入射波被转换为x偏振波，这可被视为数字状态0。当VO在临界温度（68°C）下转换为金属状态时，反射波的偏振保持不变，对应于数字状态1。通过以可编程的方式利用不同的编码序列，可以实现反射光束的任何所需线性偏振状态。此外，通过将相位梯度与偏振编码状态相结合，我们提出了一种各向异性可编程超表面来动态控制多通道反射光束。通过安排不同的编码序列，我们表明电磁反射光束可以被灵活操纵。所提出的可编程超表面为太赫兹偏振操纵、信号检测和信息通信开辟了新途径。
