• 文献标题:   Chiral triplet superconductivity on the graphene lattice
  • 文献类型:   Article
  • 作  者:   FAYE JPL, SAHEBSARA P, SENECHAL D
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:   Univ Sherbrooke
  • 被引频次:   17
  • DOI:   10.1103/PhysRevB.92.085121
  • 出版年:   2015

▎ 摘  要

Motivated by the possibility of superconductivity in doped graphene sheets, we investigate superconducting order in the extended Hubbard model on the two-dimensional graphene lattice using the variational cluster approximation (VCA) and the cellular dynamical mean-field theory (CDMFT) with an exact diagonalization solver at zero temperature. The nearest-neighbor interaction is treated using a mean-field decoupling between clusters. We compare different pairing symmetries, singlet and triplet, based on short-range pairing. VCA simulations show that the real (nonchiral), triplet p-wave symmetry is favored for small V, small onsite interaction U, or large doping, whereas the chiral combination p + ip is favored for larger values of V, stronger onsite interaction U, or smaller doping. CDMFT simulations confirm the stability of the p + ip solution, even at half-filling. Singlet superconductivity (extended s wave or d wave) is either absent or subdominant.