Open AccessEffect of retardation on localized surface plasmon resonances in a metallic nanorod
Author(s) -
Timothy J. Davis,
Kristy Ver,
Daniel E. Gómez
Publication year - 2009
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.17.023655
Subject(s) - nanorod , plasmon , surface plasmon , surface plasmon resonance , finite difference time domain method , materials science , electrostatics , surface plasmon polariton , optics , localized surface plasmon , metal , nanoparticle , molecular physics , condensed matter physics , physics , nanotechnology , quantum mechanics , metallurgy
The localized surface plasmon resonances in a metallic nanorod are determined using the "electrostatic approximation" and by a finite-difference time-domain numerical solution of Maxwell's equations. The difference between the two methods is related to the effects of re-radiation, or retardation, which is not included in the electrostatic formulation. It is shown that high-order modes in a metallic nanorod can be modeled by both methods, even beyond the point where the electrostatic method is supposed to fail. This suggests that the simple analytical expressions derived from the electrostatic approximation are valid for describing the large range of resonant modes associated with metallic nanoparticles, including dark modes.