• 文献标题:   Probing electronic lifetimes and phonon anharmonicities in high-quality chemical vapor deposited graphene by magneto-Raman spectroscopy
  • 文献类型:   Article
  • 作  者:   NEUMANN C, HALPAAP D, REICHARDT S, BANSZERUS L, SCHMITZ M, WATANABE K, TANIGUCHI T, BESCHOTEN B, STAMPFER C
  • 作者关键词:  
  • 出版物名称:   APPLIED PHYSICS LETTERS
  • ISSN:   0003-6951 EI 1077-3118
  • 通讯作者地址:   Rhein Westfal TH Aachen
  • 被引频次:   3
  • DOI:   10.1063/1.4936995
  • 出版年:   2015

▎ 摘  要

We present a magneto-Raman study on high-quality single-layer graphene grown by chemical vapor deposition (CVD) that is fully encapsulated in hexagonal boron nitride by a dry transfer technique. By analyzing the Raman D, G, and 2D peaks, we find that the structural quality of the samples is comparable with state-of-the-art exfoliated graphene flakes. From B-field dependent Raman measurements, we extract the broadening and associated lifetime of the G peak due to anharmonic effects. Furthermore, we determine the decay width and lifetime of Landau level (LL) transitions from magneto-phonon resonances as a function of laser power. At low laser power, we find a minimal decay width of 140 cm(-1) highlighting the high electronic quality of the CVD-grown graphene. At higher laser power, we observe an increase of the LL decay width leading to a saturation, with the corresponding lifetime saturating at a minimal value of 18 fs. (C) 2015 AIP Publishing LLC.