Open AccessDipole, quadrupole and octupole plasmon resonance modes in non-concentric nanocrescent/nanodisk structure: local field enhancement in the visible and near infrared regions
Author(s) -
Y. Zhang,
Tianxu Jia,
S.A. Zhang,
Feng Ding,
Zhuo Xu
Publication year - 2012
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.20.002924
Subject(s) - quadrupole , optics , dipole , infrared , plasmon , resonance (particle physics) , electric field , surface plasmon resonance , surface plasmon , materials science , wavelength , spectroscopy , localized surface plasmon , physics , molecular physics , atomic physics , nanoparticle , nanotechnology , quantum mechanics
By deviating the nanodisk from the center in the silver nanocrescent/nanodisk structure, we find that the dipole, quadrupole and octupole modes can all induce very high local electric field enhancement (LFE, more than 750) for the coupling of nanocrescent and crescent gap modes, which makes the resonant wavelengths of the non-concentric nanostructures change from the visible to near infrared regions. In addition, the LFE factor of the quadrupole mode is more than 1000, which is suitable for single molecular detection by local surface enhanced spectroscopy.