paper

Chiral triplet superconductivity on the graphene lattice

arXiv:1505.07890 · doi:10.1103/PhysRevB.92.085121

Abstract

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 -wave symmetry is favored for small , small on-site interaction or large doping, whereas the chiral combination is favored for larger values of , stronger on-site interaction or smaller doping. CDMFT simulations confirm the stability of the solution, even at half-filling. Singlet superconductivity (extended -wave or -wave) is either absent or sub-dominant.

10 pages, 8 figures

References in corpus (16)

Cited by in corpus (27)