• 文献标题:   Effect of impurities in high-symmetry lattice positions on the local density of states and conductivity of graphene
  • 文献类型:   Article
  • 作  者:   PELLEGRINO FMD, ANGILELLA GGN, PUCCI R
  • 作者关键词:   bound state, carrier density, electrical conductivity, electronic density of state, fourier transform spectra, graphene, honeycomb structure, impuritie, monolayer, scanning tunnelling spectroscopy
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121
  • 通讯作者地址:   Univ Catania
  • 被引频次:   18
  • DOI:   10.1103/PhysRevB.80.094203
  • 出版年:   2009

▎ 摘  要

Motivated by quantum chemistry calculations, showing that molecular adsorption in graphene takes place on preferential sites of the honeycomb lattice, we study the effect of an isolated impurity on the local electronic properties of a graphene monolayer, when the impurity is located on a sitelike, bondlike, or hollowlike position. We evaluate the local density of states (LDOS) as a function of energy on the impurity and on its neighboring sites, as well as in reciprocal space, at an energy corresponding to a bound state, in the three cases of interest. The latter study may be relevant to interpret the results of Fourier-transformed scanning tunneling spectroscopy, as they show which states mostly contribute to impurity-induced variations in the LDOS. We also estimate, semianalytically, the dependence of the condition for having a low-energy bound state on the impurity potential strength and width. Such results are then exploited to obtain the quasiparticle lifetime and the static conductivity in graphene in the dilute impurity limit. In particular, we recover a sublinear dependence of the conductivity on the carrier concentration as a generic impurity effect.