Frequency-switchable VO2-based coding metasurfaces at the terahertz band

• Published in: Optics communications Vol. 458
• Main Authors: Li, Jiahui, Zhang, Yating, Li, Jining, Li, Jie, Yang, Yue, Huang, Jin, Ma, Chengqi, Ma, Zhenzhen, Zhang, Zhang, Liang, Lanju, Yao, Jianquan
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2020
• Subjects: Frequency-switchable coding metasurfaces; Terahertz; Vanadium dioxide; Vanadium dioxide; Frequency-switchable coding metasurfaces; Terahertz
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/j.optcom.2019.124744

In this paper, a frequency-switchable terahertz coding metasurface is demonstrated based on the phase transition of vanadium dioxide. Temperature excitation can initiate the insulator–metal transition of vanadium dioxide, thereby changing the resonant frequency of the metal-vanadium dioxide composite unit structure, then changing the operating frequency of the entire coding metasurfaces. We first design a 1-bit coding metasurface whose working frequency can be switched between 1 THz and 1.4 THz, with a switching bandwidth of 0.4 THz. Further more, a 2-bit coding metasurface is designed, whose working frequency can be switched between 1 THz and 1.5 THz with a switching bandwidth of 0.5 THz. This work provides a new design idea for the terahertz active coding metasurfaces which opens up a broad path for coding metasurface applications such as wireless terahertz communications. •A frequency-switchable coding metasurfaces method based on vanadium dioxide is proposed.•A 1-bit coding metasurface with frequency switching between 1.4 THz and 1 THz is designed.•A 2-bit coding metasurface with frequency switching between 1.5 THz and 1 THz is designed.