Cloud Inspired White and Grey Plasmonic Metasurfaces for Camouflaged Thermal Management.

Abstract

Inspired by nature's color-driven thermal regulation mechanisms and the atmospheric radiative effects of cloud-aerosol interactions, this work presents the design of disordered metasurfaces capable of achieving white and grey plasmonic colors. This innovation advances light and thermal management technologies within the framework of stealth and camouflage applications. The white plasmonic metasurfaces emulate the cooling effects of clouds, reducing substrate temperatures by a relative -10 °C under standard solar illumination through backscattering. In contrast, transitioning to a grey state with a nanocomposite absorber suppresses backscattering and enables efficient light trapping, resulting in a relative +10  °C temperature increase compared to conventional black absorbers. These findings introduce a novel approach to localized thermal management, distinct from traditional passive cooling strategies that rely on high-emissivity materials. The metasurfaces' low-emissivity properties and visible appearance open opportunities in advanced camouflage, stealth technologies, and thermal energy solutions. Additionally, the scalable, sustainable design, realized through all-in-chamber nanofabrication via sputtering, eliminates the need for chemically intensive synthesis methods while ensuring long-term stability.