Single-plasmon interferences

Marie-Christine Dheur (1) , Eloïse Devaux (2) , Thomas W Ebbesen (2) , Alexandre Baron (3) , Jean-Claude Rodier (1) , Jean-Paul Hugonin (1) , Philippe Lalanne (4) , Jean-Jacques Greffet (1) , Gaétan Messin (5) , François Marquier (1)

1 Laboratoire Charles Fabry / Naphel
2 ISIS - Institut de Science et d'ingénierie supramoléculaires
3 CRPP - Centre de recherches Paul Pascal
4 LP2N - Laboratoire Photonique, Numérique et Nanosciences
5 Laboratoire Charles Fabry / Optique Quantique

Surface plasmon polaritons are electromagnetic waves coupled to collective electron oscillations propagating along metal-dielectric interfaces, exhibiting a bosonic character. Recent experiments involving surface plas-mons 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 entangle-ment 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.

Domains: Physics [physics]; Physics [physics]; Optics [physics.optics]

Marie-Christine Dheur, Eloïse Devaux, Thomas W Ebbesen, Alexandre Baron, Jean-Claude Rodier, et al.. Single-plasmon interferences. Science Advances , 2016, 2, pp.e1501574. ⟨10.1126/sciadv.1501574⟩. ⟨hal-01381739⟩