Electrical Control of Plasmon Resonance with Graphene

TL;DR

This paper demonstrates how electrical gating of graphene can actively control the plasmon resonance in hybrid graphene-gold nanorod structures, enabling tunable optical properties for advanced nanophotonic devices.

Contribution

It introduces a novel method for in situ electrical control of plasmon resonance using graphene integrated with nanometallic structures.

Findings

Electrical gating switches graphene's optical transitions on and off.

Significant modulation of resonance frequency and quality factor achieved.

Hybrid structures enable active control of plasmonic properties.

Abstract

Surface plasmon, with its unique capability to concentrate light into sub-wavelength volume, has enabled great advances in photon science, ranging from nano-antenna and single-molecule Raman scattering to plasmonic waveguide and metamaterials. In many applications it is desirable to control the surface plasmon resonance in situ with electric field. Graphene, with its unique tunable optical properties, provides an ideal material to integrate with nanometallic structures for realizing such control. Here we demonstrate effective modulation of the plasmon resonance in a model system composed of hybrid graphene-gold nanorod structure. Upon electrical gating the strong optical transitions in graphene can be switched on and off, which leads to significant modulation of both the resonance frequency and quality factor of plasmon resonance in gold nanorods. Hybrid graphene-nanometallic structures, as exemplified by this combination of graphene and gold nanorod, provide a general and powerful way for electrical control of plasmon resonances. It holds promise for novel active optical devices and plasmonic circuits at the deep subwavelength scale.