Using a plasmonic lens to control the emission of electrically excited light

Shuiyan Cao (1) , Médéric Lequeux (1) , Eric Le Moal (1) , Aurélien Drezet (2) , Serge Huant (2) , Gérald Dujardin (1) , Elizabeth Boer-Duchemin (1)

1 ISMO - Institut des Sciences Moléculaires d'Orsay
2 NEEL - NOF - Nano-Optique et Forces

A local, low-energy, electrical method for the excitation of localized and propagating surface plasmon polaritons (SPPs) is attractive for both fundamental and applied research. In particular, such a method produces no excitation background light and may be integrated with nanoelectronics. Here we report on the electrical excitation of SPPs through the inelastic tunneling of low-energy electrons from the tip of a scanning tunneling microscope (STM) to the surface of a two-dimensional plasmonic lens. The plasmonic structure is a series of concentric circular slits etched in a thick gold film on a glass substrate. An outgoing circular SPP wave is generated from the tip-sample junction and is scattered into light by the slits. We compare the resulting emission pattern to that observed when exciting SPPs on a thin, unstructured gold film. For optimized parameters, the light emitted from the plasmonic lens is radially polarized. We describe the effects of the slit period and number, and lens diameter on the emission pattern and we diskuss how the light beam of low divergence is formed.

Mots clés: Surface plasmon; scanning tunneling microscopy; plasmonic lens; inelastic electron tunneling; light nanosource

Domaines: Optique / photonique

Shuiyan Cao, Médéric Lequeux, Eric Le Moal, Aurélien Drezet, Serge Huant, et al.. Using a plasmonic lens to control the emission of electrically excited light. Proceedings of SPIE, the International Society for Optical Engineering, 2016, Nanophotonics VI, 9884, pp.98841Y. ⟨10.1117/12.2224472⟩. ⟨hal-01449022⟩