• 文献标题:   Probing carbon isotope effects on the Raman spectra of graphene with different C-13 concentrations
  • 文献类型:   Article
  • 作  者:   CARVALHO BR, HAO YF, RIGHI A, RODRIGUEZNIEVA JF, COLOMBO L, RUOFF RS, PIMENTA MA, FANTINI C
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121 EI 1550-235X
  • 通讯作者地址:   Univ Fed Minas Gerais
  • 被引频次:   8
  • DOI:   10.1103/PhysRevB.92.125406
  • 出版年:   2015

▎ 摘  要

A resonance Raman study of graphene samples with different C-13 isotopic concentrations and using different laser excitation energies is presented. The main Raman peaks (D, G, G*, and 2D) of graphene were measured and the dependence of their frequencies on the isotope atomic mass follows a simple harmonic oscillator relation. The G* and 2D double-resonance peak positions were measured as a function of the laser energy, and we observed that the slopes of the laser energy dependence are the same independently of isotope concentration. This result shows that isotopic substitution does not alter the electron and phonon dispersions near the K point of the graphene Brillouin zone. From the linewidth of G and 2D Raman peaks, we have also obtained a dependence of the phonon lifetime on the C-13 isotope concentration.