Polarization properties of surface plasmon enhanced photoluminescence from a single Ag nanowire.

Metallic nanowires are of great research interest due to their applications in surface plasmon polariton coupling of light. The efficiency is much dependent on the polarization of the light due to the phase matching requirement in the light-surface plasmon polariton coupling. By scanning confocal microscope, the photoluminescence from a single Ag nanowire was demonstrated strongly dependent on the excitation laser polarization, showing good consistency with the theoretical simulation. Meanwhile strong avalanche photoluminescence from a single Ag nanowire was observed when the excitation laser was polarized along the long axis of the Ag nanowire. The photoluminescence emission exhibited a polarization-sensitive spatial distribution. This may stimulate promising applications in designing polarization-controllable nanoscale plasmonic devices.