Design, simulation, and measurement of a multiband tunable metamaterial filter

Electromagnetic (EM) metamaterials/metasurface with mode conversion function or active modulation characteristics have broad application prospects in the field of optoelectronics or 6G/Terahertz (THz) communication. The current challenge is to achieve actived modulation and conversion between these modes. An EM metamaterial filter with phase-changing materia GeSb2Te5 (GST) particles is proposed, simulated, and measured. This metamaterial shows the active tunability and mode conversion by changing the temperature (synchronously changing the crystallinity of the GST arrays). At room temperature, the P1 and P2 peaks (with 90% and 52% of amplitude) are achieved at 9.28 THz and 14.18 THz. The P1 and P2 peaks can be controlled by changing the dielectric layer thickness ot the width of GST arrays in experiments. During the temperature sensitivity experiment, intermediate states of the GST arrays can be achieved by controlling the return temperature. As the temperature increases, the resonance position of the P1 peak will be replaced by the trough, thus realizing the metamaterial filter transmission window is switched between "ON " and "OFF " modes. This GST-based EM metamaterial filter provides application potential for actived mode conversion devices or 6G/THz communication.