Tunable graphene plasmonic metadevice for infrared polarization resolved spectroscopy detection

Polarization-resolved spectroscopy imaging holds significant promise in various fields. However, conventional polarization-resolved spectroscopy imaging systems often reply on separate dispersion elements, polarization splitting components, and mechanical scanning or rotating structures, resulting in bulky systems with intricate designs. The pursuit of lightweight and seamlessly integrated polarization spectroscopy imaging systems presents a critical challenge. Here, we propose an integrated polarization spectroscopy detector operating in the mid-infrared range based on a tunable graphene metasurface. Within the graphene metasurface, plasmonic resonances of graphene are excited by a gold nano-grating, allowing simultaneous modulation of spectral and polarization transmission characteristics for infrared light by tuning the Fermi energy of graphene. With the help of neural network based recovery algorithms, this system achieves pixel-level spectral detection (with a resolution below 200 nm), multi-color polarization Stokes vector analysis (with a monochromatic angular error of less than 0.1 rad), and concurrent polarization and spectroscopy detection. This research paves the way for the development of the next generation integrated infrared polarization resolved spectroscopy imaging systems.