Sub-wavelength confinement of the orbital angular momentum of light probed by plasmonic nanorods resonances.
We discuss how the topological charge of an OAM-carrying plasmon (Plasmonic Vortex) can be probed by monitoring the near-field response of plasmonic nanostructures suitably arranged inside a Plasmonic Vortex Lens. The turning "on" or "off" of four gold nanorods, detected by a Scanning Near field Optical Microscope (SNOM), acts as a fingerprint of the OAM state of the PV at the nanoscale. Different configurations are studied numerically, the integrated structure is fabricated and near field characterization is performed for a particularly meaningful case.
Marta
M
Carli
Pierfrancesco
P
Zilio
Denis
D
Garoli
Valentina
V
Giorgis
Filippo
F
Romanato
D006046:Gold / Q000737:chemistry*; D007909:Lenses; D008027:Light; D043942:Nanotubes / Q000737:chemistry*; D012542:Scattering, Radiation; D020349:Surface Plasmon Resonance / Q000379:methods*
D006046:Gold