Open AccessIntrinsic linewidth of the plasmonic resonance in a micrometric metal mesh
Author(s) -
Leonetta Baldassarre,
Michele Ortolani,
A. Nucara,
P. Maselli,
Alessandra Di Gaspare,
Valeria Giliberti,
P. Calvani
Publication year - 2013
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.21.015401
Subject(s) - laser linewidth , optics , collimated light , resonance (particle physics) , materials science , surface plasmon polariton , fano resonance , plasmon , surface plasmon , physics , laser , atomic physics
The intrinsic linewidth and angular dispersion of Surface Plasmon Polariton resonance of a micrometric metal mesh have been measured with a collimated mid-infrared beam, provided by an External Cavity tunable Quantum Cascade Laser. We show that the use of a collimated beam yields an observed resonance linewidth γ = 12 cm(-1) at the resonance frequency ν0 = 1658 cm(-1), better by an order of magnitude than with a non-collimated beam. The extremely narrow plasmon resonance attained by our mesh is then exploited to reconstruct, by varying the QCL angle of incidence θ, the angular intensity distribution f(θ) of a globar at the focal plane of a conventional imaging setup. We thus show that f(θ) is better reproduced by a Gaussian distribution than by a uniform one, in agreement with ray-tracing simulation.