Tunable broadband terahertz absorber based on graphene metamaterials and VO2

• Published in: Optical materials Vol. 114; p. 110915
• Main Authors: Zhou, Runhua, Jiang, Tingting, Peng, Zhen, Li, Zhenyuan, Zhang, Min, Wang, Shixing, Li, Ling, Liang, Huawei, Ruan, Shuangchen, Su, Hong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2021
• Subjects: Dual-controlled; Metamaterial; Terahertz; Tunable; Dual-controlled; Tunable; Terahertz; Metamaterial
• ISSN: 0925-3467
• DOI: 10.1016/j.optmat.2021.110915

A tunable broadband terahertz (THz) absorber is designed in this paper, which is composed of graphene, silica medium and phase change material Vanadium dioxide (VO2). By simultaneously changing the fermi level of graphene and conductivity of VO2, the dual-controlled absorber can be realized. The results show that the full width at half maximum of the absorption spectrum is 1.03 THz, the bandwidth with the absorptance above 90% is 0.65 THz, and the absorptance is close to 100% at 1.2 THz. Moreover, the absorptance, transmittance and reflectance of the absorber can be dynamically adjusted from 0 to 99%, 0–65%, and 0–74%, respectively. The large tunability allows the proposed absorber to be used as THz tunable filters, sensors, switches and modulators. •A broadband metamaterial absorber has been proposed based on the patterned graphene resonators.•Dual control and tunability is realized based on graphene array and phase change material vanadium dioxide.•The proposed structure can be dynamically tuned to act as an absorber or reflector.•The structure can be made to work in transmission or absorption mode by changing the conductivity of vanadium dioxide.