Nonlocal superconducting correlations in graphene in the quantum Hall regime

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-Büttiker 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.

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Cited by in corpus (15)

• Induced superconducting pairing in integer quantum Hall edge states
• Perfect crossed Andreev reflection in Dirac hybrid junctions in the quantum Hall regime
• Induced superconducting correlations in the quantum anomalous Hall insulator
• Crossed Andreev reflection in spin-polarized chiral edge states due to the Meissner effect
• Perfect crossed Andreev reflection in the proximitized graphene/superconductor/proximitized graphene junctions
• Quantized conductance with non-zero shot noise as a signature of Andreev edge state
• Andreev reflection of quantum Hall states through a quantum point contact
• Crossed Andreev reflection in topological insulator nanowire T-junctions
• SU(4) Symmetry Breaking and Induced Superconductivity in Graphene Quantum Hall Edges
• Non-local transport measurements in hybrid quantum Hall - superconducting devices
• Heat-charge separation in a hybrid superconducting quantum Hall setup
• $\Delta T$-noise in Multiterminal Hybrid Systems
• Transparent Graphene-Superconductor Interfaces: Quantum Hall and Zero Field Regimes
• Revealing Superconducting Chiral Edge Modes via Resistance Distributions
• Long-range Cooper pair splitting by chiral Majorana edge states