• 文献标题:   Long-wavelength optical phonon behavior in uniaxial strained graphene: Role of electron-phonon interaction
  • 文献类型:   Article
  • 作  者:   ASSILI M, HADDAD S
  • 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 Tunis El Manar
  • 被引频次:   4
  • DOI:   10.1103/PhysRevB.90.125401
  • 出版年:   2014

▎ 摘  要

We derive the frequency shifts and the broadening of Gamma-point longitudinal optical (LO) and transverse optical (TO) phonon modes, due to electron-phonon interaction, in graphene under uniaxial strain as a function of the electron density and the disorder amount. We show that, in the absence of a shear strain component, such interaction gives rise to a lifting of the degeneracy of the LO and TO modes which contributes to the splitting of the G Raman band. The anisotropy of the electronic spectrum, induced by the strain, results in a polarization dependence of the LO and TO modes. This dependence is in agreement with the experimental results showing a periodic modulation of the Raman intensity of the split G peak. Moreover, the anomalous behavior of the frequency shift reported in undeformed graphene is found to be robust under strain.