Open AccessSurface-plasmon-induced ultra-broadband light absorber operating in the visible to infrared range
Author(s) -
Kentaro Takatori,
Takayuki Okamoto,
Koji Ishibashi
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.001342
Subject(s) - surface plasmon , optics , materials science , broadband , plasmon , polarization (electrochemistry) , optoelectronics , visible spectrum , wavelength , infrared , absorption (acoustics) , microwave , surface plasmon polariton , octave (electronics) , physics , chemistry , quantum mechanics
We propose a novel broadband absorber that shows a strong absorption band much broader than that shown in previous work. In our proposed absorber, randomly arranged metal nanobumps are introduced in the incident-side metal layer of a metal/insulator / metal structure. The random structure converts broadband light into surface plasmons without any angular or polarization dependence. Using silver as the metal layer, we obtained an ultrawide region in which the absorption was higher than 50% in the wavelength region from 0.4 to 3.2 μm, which corresponds to a three-octave bandwidth.