Reconfigurable THz filters with integrated micro-heater

We propose a reconfigurable terahertz (THz) filter using frequency selective surfaces (FSS) combined with vanadium dioxide (VO₂) phase change materials (PCMs) integrated with micro-heater for THz applications. The integration of novel material and micro-heater with our FSS design enables simultaneous control of temperature and conductivity of the PCM film leading to transmittance profile control of the filter. The FSS filter is fabricated on a sapphire substrate and employs four metallic double-square loops with a VO₂ films between them. Simulations show excellent transmittance (-1dB loss at peak and high out-of-band rejection) and a resonance at 0.44 THz switched on and off at temperatures below and above ~70 °C, respectively.