Electrically Tunable Damping of Plasmonic Resonances with Graphene

Naresh K. Emani, Birck Nanotechnology Center, Purdue University
Ting-Fung Chung, Birck Nanotechnology Center, Purdue University
Xingjie Ni, Birck Nanotechnology Center, Purdue University
Alexander V. Kildishev, Birck Nanotechnology Center, Purdue University
Yong P. Chen, Birck Nanotechnology Center, Purdue University
Alexandra Boltasseva, Birck Nanotechnology Center, Purdue University; Technical University of Denmark

Abstract

Dynamic switching of a plasmonic resonance may find numerous applications in subwavelength optoelectronics, spectroscopy, and sensing. Graphene shows a highly tunable carrier concentration under electrostatic gating, and this could provide an effective route to achieving electrical control of the plasmonic resonance. In this Letter, we demonstrate electrical control of a plasmonic resonance at infrared frequencies using large-area graphene. Plasmonic structures fabricated on graphene enhance the interaction of the incident optical field with the graphene sheet, and the impact of graphene is much stronger at mid-infrared wavelengths. Full-wave simulations, where graphene is modeled as a 1 nm thick effective medium, show excellent agreement with experimental results.

Discipline(s)

Nanoscience and Nanotechnology