Andreev reflection near the Dirac point at Graphene - NbSe2 junction

Abstract

Despite extensive search for about a decade, specular Andreev reflection is only recently realized in bilayer graphene-superconductor interface. However, the evolution from the typical retro type Andreev reflection to the unique specular Andreev reflection in single layer graphene has not yet been observed. We investigate this transition by measuring the differential conductance at the van der Walls interface of single layer graphene and NbSe2 superconductor. We find that the normalized conductance becomes suppressed as we pass through the Dirac cone via tuning the Fermi level and bias energy, which manifests the transition from retro to non-retro type Andreev reflection. The suppression indicates the blockage of Andreev reflection beyond a critical angle of the incident electron with respect to the normal between the single layer graphene and the superconductor junction. The results are compared with a theoretical model of the corresponding setup.

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Cited by in corpus (20)

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• Enhanced Specular Andreev reflection in bilayer graphene
• Spin-polarized Specular Andreev Reflections in Altermagnets
• Quantum charge pumping through resonant crossed Andreev reflection in superconducting hybrid junction of Silicene
• Anomalous Coulomb Drag between InAs Nanowire and Graphene Heterostructures
• Andreev Reflection Spectroscopy of Topological Superconductor Candidate Nb${}_x$Bi${}_2$Se${}_3$
• Andreev Reflection and Klein Tunneling in High-Temperature Superconductor/Graphene Junctions
• Enhanced shot noise at bilayer graphene -- superconductor junction
• Tunable crossed Andreev reflection in a heterostructure consisting of ferromagnets, normal metal and superconductors
• Specular Andreev reflection and its detection
• Andreev and normal reflections in gapped bilayer graphene-superconductor junctions
• FeTe${}_{0.55}$Se${}_{0.45}$ van der Waals Tunneling Devices
• Andreev reflection in 2D relativistic materials with realistic tunneling transparency in normal-metal-superconductor junctions
• Local characterization and engineering of proximitized correlated states in graphene-NbSe${}_2$ vertical heterostructures
• Revisiting Andreev processes in superconductor-graphene-superconductor (SGS) Josephson junctions: Comparison with experimental results
• Effect of Andreev Processes on the Goos-Hänchen (GH) shift in the Graphene-Superconductor-Graphene (GSG) junctions
• Hall Effect for Dirac Electrons in Graphene Exposed to an Abrikosov Flux Lattice
• Andreev Reflections in NbN/graphene Junctions under Large Magnetic Fields