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Indexed by:期刊论文

Date of Publication:2013-06-01

Journal:PLASMONICS

Included Journals:SCIE

Volume:8

Issue:2

Page Number:669-676

ISSN No.:1557-1955

Key Words:Nano-antenna; Fabry-Perot-like resonance; Extraordinary optical transmission; Surface plasmon polaritons

Abstract:The interaction between the two perpendicular Fabry-Perot-like resonances of the antenna-dielectric-slit structure and their influences on the transmission enhancement are investigated with a finite-difference time-domain method. The transmission enhancement is found with the antenna width corresponding to a Fabry-Perot-like resonance condition in the antenna-dielectric-slit structure; otherwise, there is no such an enhancement even when the slit is positioned under the magnetic field maximum. On the other hand, the resonance characteristics of the vertical slit can also modify the field distribution in the horizontal cavity by changing the phase difference at the two antenna ends. It is shown that the enhanced transmission can be realized in a wide range of incident wavelengths from the visible to near-infrared regime for different slit geometries. The physical mechanism of extraordinary optical transmission is discussed with a theoretical dispersion relationship of surface plasmon polaritons based on a metal-insulator-metal cavity model.