Multilayer Huygens' Metasurface Absorber Toward Snapshot Multispectral Imaging

Multispectral or hyperspectral imaging requires the collection of a three-dimensional (3D) data cube that is composed of 2D spatial information and 1D spectral information of the scene. However, conventional cameras can only record 2D information, such that to obtain the 3D data cube, one needs to sacrifice either spatial or spectral resolution, or spatial or spectral scanning is required. Here, we introduce a multilayer metasurface absorber platform that may potentially allow the collection of a multispectral data cube in a single shot, without sacrificing the resolution. We design each absorber layer composed of silicon nano-resonators to support a Huygens' mode in the visible spectrum, such that each layer may detect an impinging scene only within a narrow spectral band. We envision that the multilayer metasurface absorber, if integrated with proper electronics, may be used for snapshot multispectral imaging, with potential applications in target identification with high spatial and spectral resolution.