Open AccessWideband visible-light absorption in an ultrathin silicon nanostructure
Author(s) -
Weiren Zhu,
Fajun Xiao,
Ivan D. Rukhlenko,
Junping Geng,
Xianling Liang,
Malin Premaratne,
Ronghong Jin
Publication year - 2017
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.005781
Subject(s) - metamaterial , nanostructure , materials science , optics , wideband , optoelectronics , silicon , metamaterial absorber , absorption (acoustics) , ray , wavelength , visible spectrum , nanotechnology , physics , tunable metamaterials
We design a new kind of metamaterial absorber in the form of an ultrathin silicon nanostructure capable of having wideband absorption of visible light. We show that our metamaterial can exhibit almost perfect absorption of incident light even though its thickness is several tens of times smaller than the optical wavelength. The combination of two resonant modes in a single nanostructure allows us to achieve absorptivities exceeding 80% in a wide band spanning from 437.9 to 578.3 nm. The physical origins of the two modes, elucidated via the analysis of current distribution inside the nanostructure, explain different metamaterial absorptivities for oblique incidence of TE- and TM-polarized waves. Our study opens a new prospect in designing ultrathin, yet wideband visible-light absorbers based on silicon.