Exciton-Plasmon Coupling Enhancement via Metal Oxidation

ACS Nano. 2015 Oct 27;9(10):9691-9. doi: 10.1021/acsnano.5b04974. Epub 2015 Sep 30.


In this paper, we report on the effect of metal oxidation on strong coupling interactions between silver nanostructures and a J-aggregated cyanine dye. We show that metal oxidation can sensibly affect the plexcitonic system, inducing a change in the coupling strength. In particular, we demonstrate that the presence of oxide prevents the appearance of Rabi splitting in the extinction spectra for thick spacers. In contrast, below a threshold percentage, the oxide layer results in an higher coupling strength between the plasmon and the Frenkel exciton. Contrary to common belief, a thin oxide layer seems thus to act, under certain conditions, as a coupling mediator between an emitter and a localized surface plasmon excited in a metallic nanostructure. This suggests that metal oxidation can be exploited as a means to enhance light-matter interactions in strong coupling applications.

Keywords: Rabi splitting; oxidation; plasmon; plexciton; strong coupling.

Publication types

  • Research Support, Non-U.S. Gov't