• 文献标题:   Two-body problem in graphene
  • 文献类型:   Article
  • 作  者:   SABIO J, SOLS F, GUINEA F
  • 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:   48
  • DOI:   10.1103/PhysRevB.81.045428
  • 出版年:   2010

▎ 摘  要

We study the problem of two Dirac particles interacting through nonrelativistic potentials and confined to a two-dimensional sheet, which is the relevant case for graphene layers. The two-body problem cannot be mapped into that of a single particle, due to the nontrivial coupling between the center-of-mass and the relative coordinates, even in the presence of central potentials. We focus on the case of zero total momentum, which is equivalent to that of a single particle in a Sutherland lattice. We show that zero-energy states induce features such as discontinuities in the relative wave function, for particles interacting through a step potential, and a concentration of relative density near the classical turning point, if particles interact via a Coulomb potential. In the latter case we also find that the two-body system becomes unstable above a critical coupling. These phenomena may have bearing on the nature of strong-coupling phases in graphene.