ABSTRACT
Mid-infrared absorption spectroscopy is an effective method for detecting analyte fingerprints without labeling, but the inherent loss of metals in current methods is a main issue. Here, a sensing scheme was proposed that uses an all-dielectric grating metasurface and angular scanning of polarized light, and then it was verified by numerical simulation. The proposed fingerprint detection scheme could effectively couple a guided-mode resonance spectrum peak with the characteristic peak of the analyte's phonon-polariton in the mid-infrared region, significantly enhancing the interaction between light and the analyte. The novel scheme would realize broadband enhancement to detect a variety of substances, and facilitate mid-infrared sensing and analysis of trace substances.
