• 文献标题:   Impurity effect as a probe for the pairing symmetry of graphene-based superconductors
  • 文献类型:   Article
  • 作  者:   LI YQ, ZHOU T
  • 作者关键词:   impurity effect, graphene, superconductivity
  • 出版物名称:   FRONTIERS OF PHYSICS
  • ISSN:   2095-0462 EI 2095-0470
  • 通讯作者地址:  
  • 被引频次:   2
  • DOI:   10.1007/s11467-021-1056-y
  • 出版年:   2021

▎ 摘  要

We study theoretically the single impurity effect on graphene-based superconductors. Four different pairing symmetries are discussed. Sharp in-gap resonant peaks are found near the impurity site for the d + id pairing symmetry and the p + ip pairing symmetry when the chemical potential is large. As the chemical potential decreases, the in-gap states are robust for the d + id pairing symmetry while they disappear for the p + ip pairing symmetry. Such in-gap peaks are absent for the fully gapped extended s-wave pairing symmetry and the nodal f-wave pairing symmetry. The existence of the ingap resonant peaks can be explained well based on the sign-reversal of the superconducting gap along different Fermi pockets and by analyzing the denominator of the T-matrix. All of the features may be checked by the experiments, providing a useful probe for the pairing symmetry of graphene-based superconductors.