title: Single-plasmon interferences.
abstract: Surface plasmon polaritons are electromagnetic waves coupled to collective electron oscillations propagating along metal-dielectric interfaces, exhibiting a bosonic character. Recent experiments involving surface plasmons guided by wires or stripes allowed the reproduction of quantum optics effects, such as antibunching with a single surface plasmon state, coalescence with a two-plasmon state, conservation of squeezing, or entanglement through plasmonic channels. We report the first direct demonstration of the wave-particle duality for a single surface plasmon freely propagating along a planar metal-air interface. We develop a platform that enables two complementary experiments, one revealing the particle behavior of the single-plasmon state through antibunching, and the other one where the interferences prove its wave nature. This result opens up new ways to exploit quantum conversion effects between different bosonic species as shown here with photons and polaritons.
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex, France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Dheur
authors.affiliation: Institut de Science et d'Ingénierie Supramoléculaire, CNRS, Université de Strasbourg, 67000 Strasbourg, France.
authors.forename: Eloïse
authors.identifier: 0000-0003-3220-7156
authors.initials: E
authors.lastname: Devaux
authors.affiliation: Institut de Science et d'Ingénierie Supramoléculaire, CNRS, Université de Strasbourg, 67000 Strasbourg, France.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Ebbesen
authors.affiliation: Centre de Recherche Paul Pascal, CNRS, 33600 Pessac, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Baron
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex, France.
authors.forename: Jean-Claude
authors.identifier: 0000-0003-4293-8964
authors.initials: JC
authors.lastname: Rodier
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex, France.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Hugonin
authors.affiliation: Laboratoire Photonique, Numérique et Nanosciences, Institut d'Optique, CNRS, Université de Bordeaux, 33400 Talence, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Lalanne
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex, France.
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Greffet
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex, France.
authors.forename: Gaétan
authors.initials: G
authors.lastname: Messin
authors.affiliation: Laboratoire Charles Fabry, Institut d'Optique, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex, France.
authors.forename: François
authors.initials: F
authors.lastname: Marquier
mesh_terms: D020349:Surface Plasmon Resonance
keywords: physics; plasmonic device; quantum optics; surface plasmon; wave-particle duality