Surface charge-transfer doping a quantum-confined silver monolayer beneath epitaxial graphene
arXiv:2203.03452 · doi:10.1103/PhysRevB.105.235428
Abstract
Recently the graphene/SiC interface has emerged as a versatile platform for the epitaxy of otherwise unstable, monoelemental, two-dimensional (2D) layers via intercalation. Intrinsically capped into a van der Waals heterostructure with overhead graphene, they compose a new class of quantum materials with striking properties contrasting their parent bulk crystals. Intercalated silver presents a prototypical example where 2D quantum confinement and inversion symmetry breaking entail a metal-to-semiconductor transition. However, little is known about the associated unoccupied states, and control of the Fermi level position across the bandgap would be desirable. Here, we n-type dope a graphene/2D-Ag/SiC heterostack via in situ potassium deposition and probe its band structure by means of synchrotron-based angle-resolved photoelectron spectroscopy. While the induced carrier densities on the order of cm are not yet sufficient to reach the onset of the silver conduction band, the band alignment of graphene changes relative to the rigidly shifting Ag valence band and substrate core levels. We further demonstrate an ordered potassium adlayer ( relative to graphene) with free-electron-like dispersion, suppressing plasmaron quasiparticles in graphene via enhanced metalization of the heterostack. Our results establish surface charge-transfer doping as an efficient handle to modify band alignment and electronic properties of a van der Waals heterostructure assembled from graphene and a novel type of monolayered quantum material.
arXiv comment12 pages, 6 figures; minor changes, accepted in journal
References in corpus (37)
- Electric Field Effect in Atomically Thin Carbon Films
- Two-Dimensional Gas of Massless Dirac Fermions in Graphene
- Van der Waals heterostructures
- 2D materials and van der Waals heterostructures
- Boron nitride substrates for high-quality graphene electronics
- Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
- Topological Insulators with Inversion Symmetry
- Angle-resolved photoemission spectroscopy of the cuprate superconductors
- Ultrathin epitaxial graphite: 2D electron gas properties and a route toward graphene-based nanoelectronics
- Giant Tunneling Magnetoresistance in Spin-Filter van der Waals Heterostructures
- Quasi-free Standing Epitaxial Graphene on SiC by Hydrogen Intercalation
- Observation of tunable bandgap and anisotropic Dirac semimetal state in black phosphorus
- Magic Angle Spectroscopy
- Dirac cones reshaped by interaction effects in suspended graphene
- Van der Waals metal-semiconductor junction: weak Fermi level pinning enables effective tuning of Schottky barrier
- Imaging Electronic Correlations in Twisted Bilayer Graphene near the Magic Angle
- Van der Waals heterostructures for spintronics and opto-spintronics
- A Survey of the Van Hove Scenario for High-T_c Superconductivity With Special Emphasis on Pseudogaps and Striped Phases
- The Role of Electron-electron Interactions in Graphene ARPES Spectra
- Many-body interactions in quasi-freestanding graphene
- Electron-phonon coupling and electron self-energy in electron-doped graphene: calculation of angular resolved photoemission spectra
- Comeback of epitaxial graphene for electronics: large-area growth of bilayer-free graphene on SiC
- Quantum-spin-Hall insulator with a large gap: single-layer 1T' WSe
- Overdoping graphene beyond the van Hove singularity
- Illuminating the dark corridor in graphene: polarization dependence of angle-resolved photoemission spectroscopy on graphene
- Physical origin of satellite in photoemission of doped graphene: An ab-initio GW plus cumulant study
- Semiconductor to metal transition in two-dimensional gold and its van der Waals heterostack with graphene
- Effective screening and the plasmaron bands in Graphene
- Introducing strong correlation effects into graphene by gadolinium intercalation
- Approaching ideal graphene: The structure of hydrogen-intercalated graphene on 6H-SiC(0001)
- Magnetism near half-filling of a van Hove singularity in twisted graphene bilayer
- Finding the bare band: Electron coupling to two phonon modes in potassium-doped graphene on Ir(111)
- Spin splitting and strain in epitaxial monolayer WSe on graphene
- Electronic Structure of Exfoliated and Epitaxial Hexagonal Boron Nitride
- Deconstruction of Resolution Effects in Angle-Resolved Photoemission
- Increasing the Rate of Magnesium Intercalation Underneath Epitaxial Graphene on 6H-SiC(0001)
- Plasmaron excitations in p(2x2)-K/Graphite