Open AccessPolarization-independent and omnidirectional nearly perfect absorber with ultra-thin 2D subwavelength metal grating in the visible region
Author(s) -
Wenchao Zhou,
Kaiwei Li,
Chao Song,
Peng Hao,
Mingbo Chi,
Muxin Yu
Publication year - 2015
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.23.00a413
Subject(s) - materials science , optics , grating , polarization (electrochemistry) , refractive index , guided mode resonance , optoelectronics , surface plasmon , diffraction grating , surface plasmon polariton , dielectric , surface plasmon resonance , transmittance , plasmon , physics , chemistry , nanoparticle , nanotechnology
A polarization-independent and omnidirectional nearly perfect absorber in the visible region has been proposed. The absorber is two-layer structure consisting of a subwavelength metal grating layer embedded in the high refractive index and lossless dielectric layer on the metal substrate. Extraordinary optical absorption with absorption peaks of over 99% can be achieved over the whole visible region for both TM and TE polarization. This absorption is attributed to cavity mode (CM) resonance caused by the coupled surface plasmon polaritons (SPP). Through adjusting the grating thickness, the absorption peak can be tuned linearly, which is highly advantageous to design various absorbers. Furthermore, the absorbance retains ultra-high over a wide angular range of incidence for both TM and TE polarization. This nearly perfect absorber offers great potential in the refractive index (RI) sensors, integrated photodetectors, solar cells and so on.