Metasurface sensor based on lattice mode manipulation

This study designs an asymmetric U-shaped metasurface sensor based on lattice mode manipulation, leveraging dynamic control of lattice mode resonant frequencies. Simulation results indicate that when terahertz waves are incident at 35°, the stimulated splitting of eigen-peaks yields quasi-BIC peaks with maximum Q-factor. At a 42° incident angle, coating a 1-μm-thick analyte significantly enhances the refractive-index-dependent response of quasi-BIC peaks, achieving a sensitivity of 0.5556 RIU^-1 with a linear correlation coefficient of 0.9905. This enables highly sensitive trace substance detection.