Miniature snapshot mid-infrared spectrometer based on metal-insulator-metal metasurface

Metasurfaces showcase the performance of light field manipulation at the subwavelength scale, generating tremendous applications in the field of optical imaging and sensing, especially in spectroscopic detection. Here, we demonstrate a spectral detector comprising metal-insulator-metal composite structures working in the mid-infrared band, which can effectively collect and restore target spectral characteristics in the mid-infrared band with a trained reconstruction algorithm. The proposed device consists of snapshot multichannel detection and spectral reconstruction, showing an average spectral reconstruction accuracy approaching 80% of the system. Moreover, we discuss the feasibility of applying this structural design to a miniature spectrometer over a wider infrared wavelength range by proposing a feasible design strategy. Our results provide a novel approach for low-cost and portable mid-infrared spectroscopic detection in ultracompact mid-infrared spectral imaging and sensing elements.