• 文献标题:   Plasmon-Induced Optical Anisotropy in Hybrid Graphene-Metal Nanoparticle Systems
  • 文献类型:   Article
  • 作  者:   GILBERTSON AM, FRANCESCATO Y, ROSCHUK T, SHAUTSOVA V, CHEN YG, SIDIROPOULOS TPH, HONG MH, GIANNINI V, MAIER SA, COHEN LF, OULTON RF
  • 作者关键词:   graphene, plasmonic, hybrid, hot carrier, pumpprobe, anisotropy
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Univ London Imperial Coll Sci Technol Med
  • 被引频次:   27
  • DOI:   10.1021/acs.nanolett.5b00789
  • 出版年:   2015

▎ 摘  要

Hybrid plasmonic metal-graphene systems are emerging as a class of optical metamaterials that facilitate strong light-matter interactions and are of potential importance for hot carrier graphene-based light harvesting and active plasmonic applications. Here we use femtosecond pumpprobe measurements to study the near-field interaction between graphene and plasmonic gold nanodisk resonators. By selectively probing the plasmon-induced hot carrier dynamics in samples with tailored graphene-gold interfaces, we show that plasmon-induced hot carrier generation in the graphene is dominated by direct photoexcitation with minimal contribution from charge transfer from the gold. The strong near-field interaction manifests as an unexpected and long-lived extrinsic optical anisotropy. The observations are explained by the action of highly localized plasmon-induced hot carriers in the graphene on the subresonant polarizability of the disk resonator. Because localized hot carrier generation in graphene can be exploited to drive electrical currents, plasmonic metal-graphene nanostructures present opportunities for novel hot carrier device concepts.