Blackbody radiation is intrinsically isotropic, broadband and unpolarized. However, these properties can be strongly modified using appropriate nanostructures. Here we report about the design, fabrication and characterization of an incandescent metasurface, emitting circularly polarized light in the MWIR domain, around 4.7 microns. Our device consists of a three-layer structure, where the top surface is paved with a subwavelength metallic grating following a chiral pattern. The system geometry is engineered to optimize the circular dichroism in absorption. When heated by Joule effect, the grating acts as a thermal emitter providing circularly polarized light with a polarization degree around 35%.
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