Controlling surface plasmon excitation of pair arrays of metallic nanocylinders

Applied Physics A (Impact Factor: 1.69). 11/2007; 89(2):391-395. DOI: 10.1007/s00339-007-4123-5

ABSTRACT Surface plasmon excitation of pair arrays of silver nanocylinders is studied using finite-difference time-domain simulations.
Strong local fields are generated around the nanocylinders due to excitation of localized surface plasmon and electromagnetic
fields are confined effectively in the gaps between the nanocylinders. Surface plasmon resonance and local-field enhancement
of two-pair arrays can be controlled by changing the illumination direction of the incident light due to induced asymmetric
polarization charges. Complex resonant modes could be excited with increasing number of silver nanocylinder pairs. Selective
local-field enhancement is observed in the gaps of the pairs by changing the interpair distance of four-pair arrays.

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