• 文献标题:   Broadband electromagnetic response and ultrafast dynamics of few-layer epitaxial graphene
  • 文献类型:   Article
  • 作  者:   CHOI H, BORONDICS F, SIEGEL DA, ZHOU SY, MARTIN MC, LANZARA A, KAINDL RA
  • 作者关键词:   buffer layer, electromagnetism, electronhole recombination, epitaxial layer, graphene, highspeed optical technique, infrared spectra, monolayer, optical conductivity, photoexcitation, terahertz wave spectra
  • 出版物名称:   APPLIED PHYSICS LETTERS
  • ISSN:   0003-6951
  • 通讯作者地址:   Univ Calif Berkeley
  • 被引频次:   178
  • DOI:   10.1063/1.3122348
  • 出版年:   2009

▎ 摘  要

We study the broadband optical conductivity and ultrafast carrier dynamics of epitaxial graphene in the few-layer limit. Equilibrium spectra of nominally buffer, monolayer, and multilayer graphene exhibit significant terahertz and near-infrared absorption, consistent with a model of intra- and interband transitions in a dense Dirac electron plasma. Nonequilibrium terahertz transmission changes after photoexcitation are shown to be dominated by excess hole carriers, with a 1.2 ps monoexponential decay that reflects the minority-carrier recombination time.