Thin-film perfect infrared absorbers over single- and dual-band atmospheric windows
Abstract
A thin-film perfect electromagnetic absorber with a tunable response in the infrared (IR) region is proposed using a metal-dielectric-metal configuration, which consists of a Ti top layer and a Ge spacer layer on a Ti substrate. The thin-film structure simplifies the absorber design by tuning the thicknesses of the two layers, which is suitable for large-scale fabrication by matured deposition technologies. The absorber supports perfect IR absorption with tunability from 3 µm to over 15 µm. Furthermore, the total thickness is much smaller than the wavelength, and the absorption has small iridescence. Based on this design, we demonstrated two samples with one supporting single-band absorption in the atmospheric absorption window (5–8 µm) and the other one supporting dual-band absorption in the two atmospheric transmission windows (3–5 and 8–13 µm). These absorption signatures can find applications in IR invisibility and radiative cooling.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 13, 2020
- Source ID
- 10.1364/ol.392651
Entities
People
- Chunlei Guo
- E. Michael Campbell
- Jihua Zhang
- Mohamed ElKabbash
- Ran Wei
Organizations
- Army Research Office
- Defense Advanced Research Projects Agency