Efficient Modulation of 1.55 μm Radiation with Gated Graphene on a Silicon Microring Resonator

• Published in: Nano letters Vol. 14; no. 12; pp. 6811 - 6815
• Main Authors: Qiu, Ciyuan, Gao, Weilu, Vajtai, Robert, Ajayan, Pulickel M, Kono, Junichiro, Xu, Qianfan
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 10.12.2014
• Subjects: Amplitude modulation; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic structure of nanoscale materials : clusters, nanoparticles, nanotubes, and nanocrystals; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Graphene; Materials science; Modulation; Modulators; Nanostructure; Physics; Resonators; Silicon; Specific materials; Tuning; NIR modulator; Graphene photonics; silicon microring resonator; high on/off ratio; Near infrared radiation; Electronic structure; Fermi level; Quality factor; Graphene; Resonance frequency; Silicon; Light absorption; Chip; Resonators; Gates; Semiconductor technology
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/nl502363u

The gate-controllability of the Fermi-edge onset of interband absorption in graphene can be utilized to modulate near-infrared radiation in the telecommunication band. However, a high modulation efficiency has not been demonstrated to date, because of the small amount of light absorption in graphene. Here, we demonstrate a ∼40% amplitude modulation of 1.55 μm radiation with gated single-layer graphene that is coupled with a silicon microring resonator. Both the quality factor and resonance wavelength of the silicon microring resonator were strongly modulated through gate tuning of the Fermi level in graphene. These results promise an efficient electro-optic modulator, ideal for applications in large-scale on-chip optical interconnects that are compatible with complementary metal-oxide-semiconductor technology.