Properties and Sensing Performance of All-Dielectric Metasurface THz Absorbers

We have designed, fabricated, and experimentally verified highly sensitive all-dielectric metasurface THz absorbers (AMTAs) device in the terahertz (THz) frequency range. By designing different structures of the resonant, different types of absorber, which have perfect absorption can be realized. The proposed AMTA with simplified designs is demonstrated by single-layer all-silicon array. Furthermore, the simulated results of absorption frequency changes under different refractive index demonstrate that the proposed AMTAs can act as refractive index sensors in the biochemical application, such as detection of liquid paraffin, cancer cells, and ethanol. Also, experiments of detecting different concentrations of 2, 4-Dichlorophenoxyacetic acid (2, 4-D) have demonstrated that the proposed absorbers have great potential to improve the performance in biological and chemical sensing. These results show that the AMTAs can be used as sensors, which can detect the presence of trace pesticides and residues of some chemicals in adsorption analyses, among other practical applications.