Dirac point formation revealed by Andreev tunneling in superlattice-graphene/superconductor junctions
arXiv:1906.08887 · doi:10.1103/PhysRevB.100.205429
Abstract
A graphene superlattice is formed by a one-dimensional periodic potential and is characterized by the emergence of new Dirac points in the electronic structure. The group velocity of graphene's massless Dirac fermions at the new points is drastically reduced, resulting in a measurable effect in the conductance spectroscopy. We show here that tunnel spectroscopy using a superconducting hybrid junction is more sensitive to the formation of Dirac points in the spectrum of graphene superlattices due to the additional contribution of Andreev processes. We examine the transport properties of a graphene-based superlattice--superconductor hybrid junction and demonstrate that a superlattice potential can coexist with proximity-induced superconducting correlations. Both effects contribute to change graphene's spectrum for subgap energies and, as a result, the normalized tunneling conductance features sharp changes for voltages proportional to the energy separation between the original and the newly generated Dirac points.
arXiv comment9 pages, 5 figures
References in corpus (46)
- Magic-angle graphene superlattices: a new platform for unconventional superconductivity
- Correlated Insulator Behaviour at Half-Filling in Magic Angle Graphene Superlattices
- Electronic transport in two dimensional graphene
- Cloning of Dirac fermions in graphene superlattices
- STM Spectroscopy of ultra-flat graphene on hexagonal boron nitride
- Andreev reflection and Klein tunneling in graphene
- Emergence of Superlattice Dirac Points in Graphene on Hexagonal Boron Nitride
- Veselago Lens for Electrons: Focusing and Caustics in Graphene p-n Junctions
- Dirac materials
- Specular Andreev reflection in graphene
- Hamiltonian approach to the transport properties of superconducting quantum point contacts
- Evidence for superconductivity in Li-decorated monolayer graphene
- Electronic properties of mesoscopic graphene structures: charge confinement and control of spin and charge transport
- Electron Beam Supercollimation in Graphene Superlattices
- Extra Dirac points in the energy spectrum for superlattices on single-layer graphene
- Ballistic Josephson junctions in edge-contacted graphene
- Emerging Zero Modes for Graphene in a Periodic Potential
- Quantum oscillations of the critical current and high-field superconducting proximity in ballistic graphene
- Observation of negative refraction of Dirac fermions in graphene
- Specular Interband Andreev Reflections in Graphene
- Ballistic miniband conduction in a graphene superlattice
- Transport Through Andreev Bound States in a Graphene Quantum Dot
- Superconductivity in Ca-doped graphene
- Cooper Pair Splitting by means of Graphene Quantum Dots
- Caustics due to Negative Refractive Index in Circular Graphene p-n Junctions
- Quantum Hall effect in graphene with superconducting electrodes
- p-wave triggered superconductivity in single layer graphene on an electron-doped oxide superconductor
- Induced Superconductivity in Graphene Grown on Rhenium
- Proximity coupling in superconductor-graphene heterostructures
- Transport in superlattices on single layer graphene
- Superconducting proximity effect in three-dimensional topological insulators in the presence of a magnetic field
- Odd-Frequency Triplet Superconductivity at the Helical Edge of a Toplogical Insulator
- Graphene-based electronic spin lenses
- Microscopic theory of the proximity effect in superconductor-graphene nanostructures
- Dirac Spectrum in Piecewise Constant One-Dimensional Potentials
- Tunable hybridization of Majorana bound states at the quantum spin Hall edge
- Creation of spin-triplet Cooper pairs in the absence of magnetic ordering
- Dirac Green's function approach to graphene-superconductor junctions with well defined edges
- The focusing of electron flow in a bipolar Graphene ribbon with different chiralities
- Transport spectroscopy of induced superconductivity in the three-dimensional topological insulator HgTe
- Proximity induced interface bound states in superconductor-graphene junctions
- Signatures of van Hove singularities probed by the supercurrent in a graphene - hBN superlattice
- Selective focusing of electrons and holes in a graphene-based superconducting lens
- Tunneling spectroscopy and Josephson current of superconductor-ferromagnet hybrids on the surface of a 3D TI
- Subgap states in two dimensional spectroscopy of unconventional superconductors using graphene
- Direct observation of ballistic Andreev reflection