Metasurface-based perfect reflectors for highly-sensitive infrared spectroscopy

We propose all dielectric metasurfaces for highly sensitive infrared absorption spectroscopy. The dielectric metasurfaces consisting of silicon microdisk arrays were designed and fabricated, realizing perfect reflection at certain mid-infrared wavelengths. Furthermore, tunable perfect reflection was achieved over the fingerprint region by changing diameter and height of Si disk, and also periodicity of the array, allowing us for molecular specific detection. Our dielectric perfect reflectors are promising for non-invasive molecular detection owing to ultralow heat generation under infrared irradiation.