Angle-Susceptible Narrowband Terahertz Metasurface for Thin-Film Sensing

Abstract

The plasmonic metasurface with the angle-sensitive resonance positioned in the vicinity of 0.8-0.9 THz was proposed for THz thin-film sensing and its performance under oblique illumination was numerically investigated and experimentally tested. It is shown that the metasurface can be effectively used to substitute spectral measurements for the single-wavelength ones by tracking the transmission at different angles of incidence. The proposed approach is evaluated as promising for sensing sub micron-thick analyte layers.