Liu Yan, Hu Lingxi, Liu Ming
School of Microelectronics, Shenzhen Institute of Information Technology, Shenzhen 518172, China.
Digital and Intelligent Agriculture Research Institute, School of Information Engineering, Huzhou University, Huzhou 313000, China.
Nanomaterials (Basel). 2024 Jul 15;14(14):1200. doi: 10.3390/nano14141200.
This study proposes a multifunctional absorber in the terahertz (THz) regime based on vanadium dioxide (VO) and graphene with either-or band selector applications, which can be realized by electrically and thermally controlling the Fermi energy level of graphene and vanadium dioxide, respectively. The broadband absorption can be achieved with absorptance exceeding 90%, when the VO film is in the metallic phase and the Fermi energy levels of the upper and lower graphene layers are simultaneously set to 0.6 and 0 eV, respectively. The double narrowband can be realized when the VO film is in the insulating phase and the Fermi energy levels in upper and lower graphene layers are set as 0 and 0.8 eV, respectively. By flexibly shifting between the broadband and the double narrowband, the proposed absorber can be used as an either-or band selector, corresponding optional bandwidth from 2.05 to 2.35 THz, and 3.25 to 3.6 THz. Furthermore, single narrowband absorption can be achieved by setting the conductivity of the VO film to appropriate values. The proposed absorber can be used in the THz regime in applications such as multifunctional devices, switches, cloaking objects, and band selectors.
本研究提出了一种基于二氧化钒（VO）和石墨烯的太赫兹（THz）波段多功能吸收体，可用于二选一的波段选择应用，这可以通过分别对石墨烯和二氧化钒的费米能级进行电控制和热控制来实现。当VO薄膜处于金属相且上下石墨烯层的费米能级分别同时设置为0.6和0 eV时，吸收率超过90%，可实现宽带吸收。当VO薄膜处于绝缘相且上下石墨烯层的费米能级分别设置为0和0.8 eV时，可实现双窄带吸收。通过在宽带和双窄带之间灵活切换，所提出的吸收体可作为二选一的波段选择器，对应的可选带宽为2.05至2.35 THz以及3.25至3.6 THz。此外，通过将VO薄膜的电导率设置为适当值，可实现单窄带吸收。所提出的吸收体可用于太赫兹波段的多功能器件、开关、隐身物体和波段选择器等应用中。
