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arXiv · 0903.0577

Broadband electromagnetic response and ultrafast dynamics of few-layer epitaxial graphene

H. Choi·F. Borondics·D. A. Siegel·S. Y. Zhou·M. C. Martin·A. Lanzara·R. A. Kaindl
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Abstract

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. Non-equilibrium terahertz transmission changes after photoexcitation are shown to be dominated by excess hole carriers, with a 1.2-ps mono-exponential decay that reflects the minority-carrier recombination time.

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H. Choi, F. Borondics, D. A. Siegel, S. Y. Zhou, M. C. Martin, A. Lanzara, R. A. Kaindl. 2009-05-02. Broadband electromagnetic response and ultrafast dynamics of few-layer epitaxial graphene. https://doi.org/10.1063/1.3122348

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