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arXiv · 2102.02985

A visible - infrared compatible camouflage photonic crystal with enhanced emission in 5~8 {\mu}m

Abstract

Because of surface structural constraint and thermal management requirement, visible - infrared compatible camouflage is still a great challenge. In this study, we introduce a 2D periodic aperture array into ZnO/Ag/ZnO film to realize visible-infrared compatible camouflage with a performance of thermal management by utilizing the extraordinary optical transmission in a dielectric/metal/dielectric (D/M/D) structure. Because of the high visible transmittance of the D/M/D structure, when applied on a visible camouflage coating, the beneath coating can be observed, realizing arbitrary visible camouflage. Due to the perforated Ag layer, both low emittances in 3~5 {\mu}m, 8~14 {\mu}m for infrared camouflage and high emittance in 5~8 {\mu}m for heat dissipation by radiation are achieved theoretically and experimentally. The fabricated photonic crystal exhibits high-temperature infrared camouflage in two atmospheric windows. With the same heating power of 0.40 W/cm2, this photonic crystal is 12.2 K cooler than a sample with a low-emittance surface. The proposed visible - infrared compatible camouflage photonic crystal with the performance of thermal management provides a guideline on coordinated control of light and heat, indicating a potential application in energy & thermal technologies.

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Saichao Dang, Hong Ye. 2021-02-05. A visible - infrared compatible camouflage photonic crystal with enhanced emission in 5~8 {\mu}m. https://arxiv.org/abs/2102.02985

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