Nonlinear Self-Confined Plasmonic Beams: Experimental Proof

Tintu Kuriakose (1) , Gilles Renversez (2, 3) , Virginie Nazabal (4) , Mahmoud M. R. Elsawy (2) , Nathalie . Coulon (5) , Petr Němec (6) , Mathieu Chauvet (1)

1 FEMTO-ST - Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174)
2 FRESNEL - Institut FRESNEL
3 ATHENA - ATHENA
4 ISCR - Institut des Sciences Chimiques de Rennes
5 IETR - Institut d'Électronique et des Technologies du numéRique
6 University of Pardubice

Controlling low power light beam self-confinement with ultrafast response time opens up opportunities for the development of signal processing in microdevices. The combination of a highly nonlinear medium with the tight confinement of plasmonic waves offers a viable but challenging configuration to reach this goal. In the present work, a beam propagating in a plasmonic structure that undergoes a strongly enhanced self-focusing effect is reported for the first time. The structure consists of a chalcogenide-based four-layer planar geometry engineered to limit plasmon propagation losses while exhibiting efficient Kerr self-focusing at moderate power. As expected from theory, only TM-polarized waves exhibit such a behavior. Different experimental arrangements are tested at telecom wavelengths and compared with simulations obtained from a dedicated model. The observed efficient beam reshaping takes place over a distance as low as 100 μm, which unlocks new perspectives for the development of integrated photonic devices.

Keywords: planar waveguides; nonlinear integrated plasmonics; optical Kerr effect; self-confined waves; chalcogenide glass; modeling; Finite element method FEM

Domains: Physics [physics]; Physics [physics]; Optics [physics.optics]; Chemical Sciences; Nonlinear Sciences [physics]; Pattern Formation and Solitons [nlin.PS]

Tintu Kuriakose, Gilles Renversez, Virginie Nazabal, Mahmoud M. R. Elsawy, Nathalie . Coulon, et al.. Nonlinear Self-Confined Plasmonic Beams: Experimental Proof. ACS photonics, 2020, 7 (9), pp.2562-2570. ⟨10.1021/acsphotonics.0c00906⟩. ⟨hal-02961176⟩