Verification of a 6G terahertz tunable metasurface filter based on phase change materials and its sensing performance

Here, a metasurface filter based on phase change materials is proposed and validated. Based on the temperature phase transition characteristic of vanadium dioxide (VO₂), this metasurface filter obtains four filter bands at temperatures lower than 68 °C. When the temperature is higher than 68 °C, two new filter bands are achieved and the original four filter bands are retained. The active modulation and conversion between two filter states by changing the temperature are achieved. In addition, these filter bands are able to achieve tunability (both frequency and amplitude are dependent on temperature conditions). These results demonstrate the tunability and temperature sensing characteristics of the metasurface filter.