Ultrahigh performance passive radiative cooling by hybrid polar dielectric metasurface thermal emitters

Real-world passive radiative cooling requires highly emissive, selective, and omnidirectional thermal emitters to maintain the radiative cooler at a certain temperature below the ambient temperature while maximizing the net cooling power. Despite various selective thermal emitters have been demonstrated, it is still challenging to achieve these conditions simultaneously because of the extreme difficulty in controlling thermal emission of photonic structures in multidimension. Here we demonstrated hybrid polar dielectric metasurface thermal emitters with machine learning inverse design, enabling a high emissivity of ~0.92 within the atmospheric transparency window 8–13 μm, a large spectral selectivity of ~1.8…

• NN
  National Natural Science Foundation of China

  Awards: 22YF1430200, 62175154
• PF
  Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning