• 文献标题:   Enhanced Andreev reflection in gapped graphene
  • 文献类型:   Article
  • 作  者:   MAJIDI L, ZAREYAN M
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121 EI 1550-235X
  • 通讯作者地址:   IASBS
  • 被引频次:   11
  • DOI:   10.1103/PhysRevB.86.075443
  • 出版年:   2012

▎ 摘  要

We theoretically demonstrate unusual features of superconducting proximity effect in gapped graphene that presents a pseudospin symmetry-broken ferromagnet with a net pseudomagnetization. We find that the presence of a band gap makes the Andreev conductance of graphene superconductor/pseudoferromagnet (S/PF) junction to behave similar to that of a graphene ferromagnet-superconductor junction. The energy gap Delta(N) can enhance the pseudospin inverted Andreev conductance of S/PF junction to reach a limiting maximum value for Delta(N) >> mu, which depending on the bias voltage can be larger than the value for the corresponding junction with no energy gap. We further demonstrate a damped-oscillatory behavior for the local density of states of the PF region of S/PF junction and a long-range crossed Andreev reflection process in PF/S/PF structure with antiparallel alignment of pseudomagnetizations of PFs, which confirm that, in this respect, the gapped normal graphene behaves like a ferromagnetic graphene.