title: Exciton-Plasmon Coupling Enhancement via Metal Oxidation.
abstract: 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.
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.|Dipartimento di Matematica e Fisica "Ennio De Giorgi" Strada Provinciale Lecce-Monteroni, Universitá del Salento , Campus Ecotekne, Lecce, Italy 73100.
authors.forename: Francesco
authors.initials: F
authors.lastname: Todisco
authors.affiliation: Center for Biomolecular Nanotechnologies@UNILE , Istituto Italiano di Tecnologia, Via Barsanti, Arnesano, Italy 73010.
authors.forename: Stefania
authors.initials: S
authors.lastname: D'Agostino
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.|Dipartimento di Matematica e Fisica "Ennio De Giorgi" Strada Provinciale Lecce-Monteroni, Universitá del Salento , Campus Ecotekne, Lecce, Italy 73100.
authors.forename: Marco
authors.initials: M
authors.lastname: Esposito
authors.affiliation: Departamento de Fìsica Teòrica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autònoma de Madrid Calle Francisco Tomás y Valiente , 7 Madrid, Spain E-28049.
authors.forename: Antonio I
authors.initials: AI
authors.lastname: Fernández-Domínguez
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.
authors.forename: Milena
authors.initials: M
authors.lastname: De Giorgi
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.
authors.forename: Dario
authors.initials: D
authors.lastname: Ballarini
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.|Center for Biomolecular Nanotechnologies@UNILE , Istituto Italiano di Tecnologia, Via Barsanti, Arnesano, Italy 73010.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Dominici
authors.affiliation: Dipartimento di Matematica e Fisica "Ennio De Giorgi" Strada Provinciale Lecce-Monteroni, Universitá del Salento , Campus Ecotekne, Lecce, Italy 73100.
authors.forename: Iolena
authors.initials: I
authors.lastname: Tarantini
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.
authors.forename: Massimo
authors.initials: M
authors.lastname: Cuscuná
authors.affiliation: Center for Biomolecular Nanotechnologies@UNILE , Istituto Italiano di Tecnologia, Via Barsanti, Arnesano, Italy 73010.|Istituto Nanoscienze, CNR, Euromediterranean Center for Nanomaterial Modelling and Technology (ECMT) , Via Arnesano, Lecce, Italy 73100.
authors.forename: Fabio
authors.initials: F
authors.lastname: Della Sala
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.|Dipartimento di Matematica e Fisica "Ennio De Giorgi" Strada Provinciale Lecce-Monteroni, Universitá del Salento , Campus Ecotekne, Lecce, Italy 73100.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Gigli
authors.affiliation: CNR NANOTEC, Istituto di Nanotecnologia Polo di Nanotecnologia c/o Campus Ecotekne, Via Monteroni Lecce, Via Monteroni, Lecce, Italy 73100.
authors.forename: Daniele
authors.initials: D
authors.lastname: Sanvitto
keywords: Rabi splitting; oxidation; plasmon; plexciton; strong coupling