Effective, angle-independent radiative cooler based on one-dimensional photonic crystal.

A simple and low-cost radiative cooler based on one-dimensional photonic crystal is proposed in this work, which has an average emissivity of 96% within the atmospheric transparency window (8-13 mu m). The ultra-broadband emissivity property is realized by constructing the strongly overlapped optical resonances with a tandem structure composed of two lossy materials while an additional lossless material is adopted as the top layer to reduce the Fresnel reflection of the whole structure. The maximum cooling power density of the fabricated radiative cooler can reach 113.0W/m(2) at night. When integrated with an excellent solar reflector that can reflect 97% incident solar power, it theoretically has the maximum cooling power of 83.0 W/m(2) in the case of solar irradiance up to 1000 W/m(2) at noon. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement