Dual-pattern broadband polarization converter in THz band based on graphene and VO2 hybrid metasurface.

• Designed a versatile polarization conversion metasurface. • Designed metasurface can switch between transmissive linear-to-linear polarization conversion and reflective quarter-wave plate (QWP). • Designed metasurface with simpler structure and wider bandwidth than similar structures. We propose a dual-pattern broadband polarization converter in the terahertz band using a vanadium dioxide (VO 2) and graphene metasurface. The converter can be switched between transmission and reflection patterns by controlling the phase of VO 2. In the insulating state of VO 2 and with the Fermi energy of graphene (E f) set to 1 eV, the converter works in transmission mode and can convert linearly polarized waves. In the metallic state of VO 2 and with E f set to = 0 eV, the converter works in reflection mode and can function as a quarter-wave plate. The proposed converter is expected to have applications in integrated devices that control the polarization state of terahertz waves. [ABSTRACT FROM AUTHOR]