Differential reflectivity spectroscopy on single patch nanoantennas

Abstract

We present an experimental technique adapted to characterize individual metallic nanostructure in terms of differential reflectivity spectroscopy. We analyze gold patch nanoantennas holding different morphological properties. Our experimental methodology shows steady and reliable results consistent with classical analytical approximations and simulation methods. This technique allows to identify absorption properties of metallic nanostructures commonly associated to surface plasmon resonances. By contrasting the light absorbed solely by the metallic antenna with respect to a surrounding reference medium, we found that some antennas show absorption of almost 50% of the incident light across the range of the visible spectrum. Plasmonic patch nanoantennas are promising systems in which the confinement of the electromagnetic field inside the dielectric gap strongly modify the local density of states.

Fabrication of Efficient Single‐Emitter Plasmonic Patch Antennas by Deterministic In Situ Optical Lithography using Spatially Modulated Light

“…Analyzing QD emission as a function of pump intensity, Zhang et al have reported a very similar trend [36]; here we observe higher nonlinearity and a larger absorption cross-section due to the antenna. Plasmonic interactions provide efficient ways of trapping and propagating light [37,38,39], which increases the effective absorption cross-section of these antennas [40,41]. Our measurements reveal a 1000-fold increase in the absorption cross-section due to the antenna.…”

“…Analyzing QD emission as a function of pump intensity, Zhang et al have reported a very similar trend; [36] here we observe higher nonlinearity and a larger absorption cross-section to the antenna. Plasmonic interactions provide efficient ways of trapping and propagating light, [37][38][39] which increases the effective absorption cross-section of these antennas. [40,41,46,47] Our measurement shows that in comparison to the absorption cross-section of a typical QD (see the Supporting Information), the absorption cross-section of the presented QD+antenna system is 1000 times more, or in other words, the presented antenna induces a 1000-fold effective increase in the emitter absorption cross-section.…”