Open AccessDesign of extraordinary-optical-transimission refractive-index sensor of subwavelength metallic slit array based on a Fabry-Perot model
Author(s) -
Zhiwen Zeng,
Haitao Liu,
Siwen Zhang
Publication year - 2012
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.61.200701
Subject(s) - refractive index , optics , slit , transmittance , transmission (telecommunications) , extraordinary optical transmission , materials science , anomaly (physics) , fabry–pérot interferometer , rayleigh scattering , physics , resonance (particle physics) , telecommunications , surface plasmon , wavelength , plasmon , atomic physics , computer science , surface plasmon polariton , condensed matter physics
The refractive index sensing properties of a period array of subwavelength metallic slits in water environment are investigated. The transmission spectra of the slit array are calculated with a rigorous fully-vectorial method. A simple semi-analytical Fabry-Perot model that can accurately reproduce the rigorous fully-vectorial data is built up. We find that the transmission peak becomes sharpest as it is exactly located at the Rayleigh anomaly position, which is explained based on the resonance condition derived from the model. The method to design the slit array to achieve this sharpest transmission peak is presented. The full width at half-maximum (δλ) of the designed transmission peak can be as low as 0.01 nm, which corresponds to a refractive-index measurement uncertainty (δns) of 2× 10-6 RIU. The influences of array period, slit width and incident angle on the designed sensitivity, δλ, δns and peak transmittance of the sensor are systematically provided.