Liu Hongyao, Wang Panpan, Wu Jiali, Yan Xin, Yuan Xueguang, Zhang Yangan, Zhang Xia
State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing 100876, China.
School of Information and Communication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China.
Micromachines (Basel). 2021 May 27;12(6):619. doi: 10.3390/mi12060619.
In this paper, a switchable and dual-tunable terahertz absorber based on patterned graphene and vanadium dioxide is proposed and analyzed. By controlling the Fermi level of graphene and the temperature of vanadium dioxide, the device's function can be switched and its absorbing properties can be tuned. When the vanadium dioxide is in an insulator state, the device can be switched from near-total reflection (>97%) to ultra-broadband absorption (4.5-10.61 THz) as the Fermi level of graphene changes from 0 to 0.8 eV. When the vanadium dioxide is changed to a metal state, the device can act as a single-band absorber (when the Fermi level of graphene is 0 eV) and a dual-band absorber with peaks of 4.16 THz and 7.3 THz (when the Fermi level of graphene is 0.8 eV). Additionally, the absorber is polarization-insensitive and can maintain a stable high-absorption performance within a 55° incidence angle. The multilayered structure shows great potential for switchable and tunable high-performance terahertz devices.
本文提出并分析了一种基于图案化石墨烯和二氧化钒的可切换双可调太赫兹吸收器。通过控制石墨烯的费米能级和二氧化钒的温度，可以切换器件的功能并调节其吸收特性。当二氧化钒处于绝缘状态时，随着石墨烯的费米能级从0变为0.8 eV，器件可以从近全反射（>97%）切换到超宽带吸收（4.5 - 10.61太赫兹）。当二氧化钒转变为金属状态时，器件可以作为单频吸收器（当石墨烯的费米能级为0 eV时）以及具有4.16太赫兹和7.3太赫兹峰值的双频吸收器（当石墨烯的费米能级为0.8 eV时）。此外，该吸收器对偏振不敏感，并且在55°入射角范围内能够保持稳定的高吸收性能。这种多层结构在可切换和可调谐的高性能太赫兹器件方面展现出巨大潜力。
