Open AccessNanometric control of the distance between plasmonic nanoparticles using optical forces
Author(s) -
Borja Sepúlveda,
Joan Alegret,
Mikael Käll
Publication year - 2007
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.15.014914
Subject(s) - optical force , surface plasmon resonance , rayleigh scattering , wavelength , materials science , optics , plasmon , ray , polarization (electrochemistry) , nanoparticle , plasmonic nanoparticles , surface plasmon , optoelectronics , optical tweezers , nanotechnology , physics , chemistry
We theoretically analyze the optical forces between two nearby silver nanoparticles for the case when the wavelength of the incoming light is close to the localized surface plasmon resonance (LSPR). It is shown that the optical force between the nanoparticles is enhanced by the LSPR and that it changes from attractive to repulsive for wavelengths slightly shorter than the resonance when the polarization of the incident light is parallel to the axis of the dimer. This behavior can be utilized to generate a stable separation distance between the nanoparticles. In the Rayleigh limit, the equilibrium distance is uniquely determined by the real part of the particle polarizability and the wavelength of the incident light. The results suggest that near-field optical forces can be used to manipulate and organize plasmonic nanoparticles with a tunable spatial resolution in the nanometer regime.