Switchable Dual-Function Terahertz Metamaterial Device Based on Vanadium Dioxide

Abstract

On the basis of the temperature-controlled phase change properties of vanadium dioxide (VO2), a dual-functional terahertz metamaterial device is proposed. The device can be switched between an absorber and a polarization converter. Simulation results demonstrate that the device acts as a terahertz wave absorber when the VO2 is in the metallic state, and the reflected extinction ratio is less than −15 dB in the frequency range between 1.07 and 1.19 THz. Moreover, the absorption performance is insensitive to polarization. When the VO2 is in the insulated state, the device behaves as a polarization converter, which can convert line-polarized light to cross-polarized light. The polarization conversion rate of the device is over 90% in the frequency range between 1.43 and 1.51 THz. The proposed dual-functional metamaterial device with tunable and diverse functions has broad and potentially useful uses in areas such as terahertz detection, modulation, and switching.