Thermally reconfigurable extraordinary terahertz transmission using vanadium dioxide

We numerically demonstrate a reconfigurable extraordinary terahertz transmission based on a phase-change material of vanadium dioxide ( V O 2 ). The proposed hybrid metasurface is composed of an array of subwavelength apertures perforated on a gold film. The holes are partially filled with annular V O 2 and gold disks to control the effective aperture area and the modes inside the aperture. Switching between the insulator and the metallic phase of V O 2 provides a convenient way to shift the transmission window. We present two designs offering redshift or blueshift of the extraordinary terahertz transmission. Upon phase transition from the insulator to the metallic phase, in the first design, the transmission peak redshifts from 1.02 to 0.82 THz while in the second design the transmission peak blueshifts from 0.71 to 0.77 THz. Furthermore, the transmission level and resonance frequency can be modulated by controlling the partial phase transition of the V O 2 . The potential applications for the proposed structures are terahertz modulators and reconfigurable filters.