Generation of Radially Polarized Single Photons with Plasmonic Bullseye Antennas

Radially polarized optical beams are desirable in many applications because of their property to generate longitudinally fields when being strongly focused. Single-photon sources however normally limited the generation linearly photons due dipolar nature. Here, we report on emission radially single from a nitrogen-vacancy (NV) center nanodiamond (ND) coupled bull’s-eye plasmonic antenna. Design optimization and characterization antennas consisting polymer circular nanoridges deterministically fabricated silica protected silver film around an NV-ND emitter reported. We demonstrate with numerical simulations that collection efficiency for emitted at design wavelength can exceed 80% optimized structures. Analysis angular distribution indicates that, even limiting detection main lobe by using 0.2 NA objective, overreach 55%. A 3-fold enhancement total number detected is experimentally observed single-photon Generation suggests new interesting possibilities imaging sensing.