Near-unity ultra-wideband thermal infrared emission for space solar power radiative cooling

We report the design, fabrication and characterization of ultrathin metasurfaces that exhibit wideband 300 K thermal emissivity. The emissive behavior of these structures is almost independent of the emission angle. Our ultralight subwavelength-thickness metasurfaces can be fabricated relatively easily and are excellent candidates for radiative cooling in space applications.