English

Nonlocal superconducting correlations in graphene in the quantum Hall regime

Mesoscale and Nanoscale Physics 2018-05-16 v1 Superconductivity

Abstract

We study Andreev processes and nonlocal transport in a three-terminal graphene-superconductor hybrid system under a quantizing perpendicular magnetic field [G.-H. Lee et al., Nature Phys. 13, 693 (2017)]. We find that the amplitude of the crossed Andreev reflection (CAR) processes crucially depends on the orientation of the lattice. By employing Landauer-B\"{u}ttiker scattering theory, we find that CAR is generally very small for a zigzag edge, while for an armchair edge it can be larger than the normal transmission, thereby resulting in a negative nonlocal resistance. In the case of an armchair edge and with a wide superconducting region (as compared to the superconducting coherence length), CAR exhibits large oscillations as a function of the magnetic field due to interference effects. This results in sign changes of the nonlocal resistance.

Keywords

Cite

@article{arxiv.1803.03043,
  title  = {Nonlocal superconducting correlations in graphene in the quantum Hall regime},
  author = {Michael Beconcini and Marco Polini and Fabio Taddei},
  journal= {arXiv preprint arXiv:1803.03043},
  year   = {2018}
}