• 文献标题:   Phonon-limited electron mobility in graphene calculated using tight-binding Bloch waves
  • 文献类型:   Article
  • 作  者:   SULE N, KNEZEVIC I
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF APPLIED PHYSICS
  • ISSN:   0021-8979 EI 1089-7550
  • 通讯作者地址:   Univ Wisconsin
  • 被引频次:   23
  • DOI:   10.1063/1.4747930
  • 出版年:   2012

▎ 摘  要

We present a calculation of the electron-phonon scattering rates in ideal monolayer graphene using the third-nearest-neighbor (3NN) tight-binding (TB) electronic Bloch wave functions formed by the analytical carbon 2p(z) orbitals with an effective nuclear charge of Z(eff) = 4:14. With these wave functions, the band structure is also represented very accurately over the entire Brillouin zone. By fitting the rates calculated using the TB Bloch wave functions to those calculated by density functional theory (DFT), we extract the "bare" acoustic and optical deformation potential constants, which do not include the effect of the wave function overlap or substrate, to be D-ac = 12 eV and D-op = 5 x 10(9) eV/cm, respectively. The phonon-limited electron mobility based on these rates is calculated within the relaxation-time approximation and presented for various doping densities and temperatures, with representative values being of order 10(7) cm(2)/Vs (50 K) and 10(6) cm(2)/Vs (300 K) at the carrier density of 10(12) cm(-2). The electron mobility values are in good agreement with those reported by DFT and exceed the experimentally obtained values, where the substrate plays an important role. We discuss the utility of the 3NN TB approximation for transport calculations in graphene-based nanostructures. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4747930]