Open AccessTransmission resonances of compound metallic gratings with two subwavelength slits in each period
Author(s) -
Dong Xiang,
Lingling Wang,
Xiaofei Li,
Liu Wang,
Xiang Zhai,
Zhonghe Liu,
Weiwei Zhao
Publication year - 2011
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.19.002187
Subject(s) - optics , extraordinary optical transmission , transmission (telecommunications) , resonance (particle physics) , wavelength , dielectric , diffraction grating , materials science , phase (matter) , transmission coefficient , physics , guided mode resonance , surface plasmon , optoelectronics , plasmon , surface plasmon polariton , telecommunications , particle physics , quantum mechanics , computer science
Based on the finite-difference time-domain method, we investigate the transmission resonances of compound metallic gratings with two subwavelength slits filled with different dielectrics inside each period in the visible and near infrared regions. The results show that the transmission spectrum is almost a compound of that of two corresponding simple gratings expect for the transmission feature at a certain resonant wavelength, where the Fabry-Pérot (FP)-like phenomena have been found both inside the two slits, but the orders of the FP-like modes are different. If the order of the FP-like mode inside one slit is one bigger than inside the other, the intensity of the transmission will be significantly weakened. We attribute this phenomenon to the phase resonance because the phases at the exits of the two slits are opposite to each other.