A novel terahertz modulator based on nested square rings and vanadium oxide phase-change materials

This paper proposes a novel terahertz metamaterial modulator utilizing vanadium dioxide phase-change materials, which adopts three nested square split rings as a unit cell. The modulator can achieve dual functions of band-stop filter and bandpass filter by vanadium dioxide filled in the gap of split ring changing phase. The simulation results show that the central frequency of the modulator is around 0.83 THz, whether the modulator is at band-stop state or band-pass state. The modulator shows that the -3 dB bandwidth reaches to 30 GHz at the state of band-pass, and that the -20 dB bandwidth reaches to 160 GHz at the state of band-stop.