Nonlocal superconducting correlations in graphene in the quantum Hall regime

Article

关键词: MAGNETIC-FIELDS;    ANDREEV REFLECTION;    JUNCTIONS;    TRANSPORT;   

DOI  :  10.1103/PhysRevB.97.201403

来源: SCIE

【 摘 要 】

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., Nat. 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-Buttiker 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.

【 授权许可】

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