Abstract
Windows with passive multilayer coatings can allow less energy to be
used when maintaining comfortable indoor temperatures. As a type of
effective solar energy management, these coatings can prevent the
generation of excessive heat inside buildings or vehicles by
reflecting near-infrared solar radiation (750–2000 nm) while retaining
visible light transmission (400–750 nm) over a large range of viewing
angles. To prevent overheating, they must also reflect rather than
absorb near-infrared radiation. A transparent heat-shielding window is
numerically and experimentally demonstrated in this study. High visual
transparency (77.2%), near-infrared reflectance (86.1%), and low
infrared absorption (<20%) over a wide range of oblique
incident angles were achieved using nanometer-scale cross-shaped
metamaterials manufactured by electron beam lithography. Furthermore,
high terahertz transmittance (up to 82%) was also achieved for 6G
communication system applications.
Funder
Core Research for Evolutional Science and
Technology
Japan Science and Technology
Agency
Subject
Atomic and Molecular Physics, and Optics,Engineering (miscellaneous),Electrical and Electronic Engineering