Design of Seal Type High Sensitivity Terahertz Metasurface Refractive Index Sensor Based on Indium Antimonide
A terahertz metasurface refractive index sensor based on indium antimonide material is theoretically investigated and experimen-tally verified.The reflection performance of the reflector is analyzed by using the frequency-domain finite difference method,and the thick-ness of the material and the length and width of the etched structure period are optimized to achieve high sensitivity and reflectivity.The simulation results show that the maximum refractive index sensitivity and the figure of merit of this metasurface sensor are 620 GHz/RIU and 25.2,respectively in the 0-1.0 THz frequency band,which is three times more sensitive than the traditional sensor.The refractive in-dex sensor provides a high sensitive detection method for protein concentration measurement,virus detection,and determination of cancer cells and their markers.