Xiao Binggang, Wei Zhonghua, Ge Panpeng, Wang XinYi, Xiao Lihua, Qin Jianyuan, Zhang Dongping, Mi Hongmei, Yu Jiabin
Appl Opt. 2024 Apr 10;63(11):2882-2891. doi: 10.1364/AO.515723.
In this paper, a graphene-vanadium dioxide-based reconfigurable metasurface unit structure is proposed. Using the change at a graphene Fermi energy level on the surface of the unit structure to satisfy the 2-bit coding condition, four reflection units with a phase difference of 90 can be discovered. The modulating impact of the multi-beam reflection wave with 1-bit coding is then confirmed. Then we study the control of a single-beam reflected wave by metasurfaces combined with a convolution theorem in a 2-bit coding mode. Finally, when vanadium dioxide is in an insulating condition, the structure can also be transformed into a terahertz absorber. It is possible to switch between a reflection beam controller and a terahertz multifrequency absorber simply by changing the temperature of the vanadium dioxide layer without retooling a new metasurface. Moreover, compared with the 1-bit coded metasurface, it increases the ability of single-beam regulation, which makes the device more powerful for beam regulation.
本文提出了一种基于石墨烯 - 二氧化钒的可重构超表面单元结构。利用单元结构表面石墨烯费米能级的变化来满足2位编码条件，可以发现四个相位差为90°的反射单元。然后证实了1位编码对多波束反射波的调制影响。接着我们研究了在2位编码模式下，超表面结合卷积定理对单波束反射波的控制。最后，当二氧化钒处于绝缘状态时，该结构还可转变为太赫兹吸收器。只需改变二氧化钒层的温度，就可以在不重新制作新超表面的情况下，在反射波束控制器和太赫兹多频吸收器之间进行切换。此外，与1位编码超表面相比，它增强了单波束调节能力，这使得该器件在波束调节方面更加强大。
