Low‐Loss Spectrum‐Disparate Discrete Superatomic T2SL Infrared Computing Multispectral Metasurface Detector

Abstract The acquisition and processing of spectral information are fundamental for analyzing light‐matter interactions. However, conventional detectors are unable to sense and process spectral information directly at the pixel level. This study presents a GaSb/Ti/Au discrete superatomic metasurface (DSM) compatible with Type‐II superlattice (T2SL) infrared detectors, integrated with a computational spectral reconstruction framework for multispectral infrared detection. The proposed system addresses key limitations of traditional multispectral infrared detectors, such as low energy utilization efficiency and limited accuracy in computational spectral reconstruction. The results demonstrate that the DSM significantly improves energy utilization efficiency (up to 87.6%) while maintaining a low mean spectral correlation mean (≈0.3). When combined with a compressive sensing‐based spectral reconstruction algorithm, the system achieves high reconstruction fidelity values of 100%, 99.9%, 99.12%, and 97.16% for single‐peak narrowband, multi‐peak narrowband, broadband, and random spectral signals, respectively, with a spectral reconstruction resolution as fine as 3 nm. Experimental characterization of the fabricated metasurface infrared detector confirms its ability to produce distinctspectral response variations. This research provides a novel pathway for multispectral infrared imaging and spectral analysis, and supports the development of high‐efficiency T2SL‐based computational multispectral infrared detectors.