Electrical Control of Optical Plasmon Resonance with Graphene
Abstract
Surface plasmon has the unique capability to concentrate light into subwavelength volume. Active plasmon devices using electrostatic gating can enable flexible control of the plasmon excitations,6 which has been demonstrated recently in terahertz plasmonic structures. Controlling plasmon resonance at optical frequencies however, remains a significant challenge because gate-induced free electrons have very weak responses at optical frequencies. Here we achieve efficient control of nearinfrared plasmon resonance in a hybrid graphene-gold nanorod system. Exploiting the uniquely strong and gate-tunable optical transitions of graphene, we are able to significantly modulate both the resonance frequency and quality factor of gold nanorod plasmon. Our analysis shows that the plasmon-graphene coupling is remarkably strong: even a single electron in graphene at the plasmonic hotspot could have an observable effect on plasmon scattering intensity. Such hybrid graphene-nanometallic structure provides a powerful way for electrical control of plasmon resonances at optical frequencies and could enable novel plasmonic sensing down to single charge transfer events.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2012
- Accession Number
- ADA585704
Entities
People
- Alex Zettl
- Baisong Geng
- David J. Cho
- Feng Wang
- Hyungmok Son
- Jonghwan Kim
- Kwanpyo Kim
- Sufei Shi
- Will Regan
- Yuen-ron Shen
Organizations
- University of California, Berkeley