• 文献标题:   Linear response and the Thomas-Fermi approximation in undoped graphene
  • 文献类型:   Article
  • 作  者:   BREY L, FERTIG HA
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121
  • 通讯作者地址:   CSIC
  • 被引频次:   15
  • DOI:   10.1103/PhysRevB.80.035406
  • 出版年:   2009

▎ 摘  要

We analyze the range of validity of Thomas-Fermi theory for describing charge-density modulations induced by external potentials in neutral graphene. We compare exact results obtained from a tight-binding calculation with those of linear-response theory and the Thomas-Fermi approximation. For experimentally interesting ranges of size and density amplitudes (electron densities less than similar to 10(11) cm(-2), and spatial length scales below similar to 20 nm), linear response is significantly more accurate than Thomas-Fermi theory.