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

作　　者：Yinan Zhang Yinggang Chen Tong Wang Qian Zhu Min Gu 

机构地区：[1]Institute of Photonic Chips,University of Shanghai for Science and Technology,Shanghai 200093,China [2]Centre for Artificial-Intelligence Nanophotonics,School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China

出　　处：《Opto-Electronic Advances》2024年第4期17-25,共9页光电进展（英文）

基　　金：supported by the National Natural Science Foundation of China(NSFC)(Grant No.62175154);the Shanghai Pujiang Program(20PJ1411900);the Shanghai Science and Technology Program(21ZR1445500);the Shanghai Yangfan Program(22YF1430200);the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning.

摘　　要：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 sim-ultaneously 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,en-abling a high emissivity of~0.92 within the atmospheric transparency window 8-13μm,a large spectral selectivity of~1.8 and a wide emission angle up to 80 degrees,simultaneously.This selective and omnidirectional thermal emitter has led to a new record of temperature reduction as large as~15.4°C under strong solar irradiation of~800 W/m2,signific-antly surpassing the state-of-the-art results.The designed structures also show great potential in tackling the urban heat island effect,with modelling results suggesting a large energy saving and deployment area reduction.This research will make significant impact on passive radiative cooling,thermal energy photonics and tackling global climate change.

关 键 词：radiative cooling dielectric metasurfaces machine learning thermal emitters 

分 类 号：TB65[一般工业技术—制冷工程]