Metamaterial absorber for frequency selective thermal radiation

Here, a polarization-independent frequency-selective thermal emitter (FSTE) in the mid-infrared range was proposed and fabricated based on metamaterial absorber. FSTE can significantly improve the capability of infrared stealth and heat radiation. The simulated results show that the proposed FSTE has high reflectivity in the two atmospheric windows (3.0–5.0 μm and 8.0–14.0 μm) for normal incidence waves, and the emissivity is suppressed completely under 0.06. In the atmosphere absorption band of 5.5–7.6 μm, the FSTE exhibits high absorption and high emissivity, which can passively cool themselves through radiative emission of heat to outer space. E-beam lithography was used to fabricate the FSTE and the infrared emissivity characteristics were analyzed. The experimental results have consistency with the simulation results.