Origin of the flat band in heavily Cs doped graphene

Abstract

A flat energy dispersion of electrons at the Fermi level of a material leads to instabilities in the electronic system and can drive phase transitions. Here we introduce a method to induce a flat band in two-dimensional (2D) materials. We show that the flat band can be achieved by sandwiching the 2D material by two cesium (Cs) layers. We apply this method to monolayer graphene and investigate the flat band by a combination of angle-resolved photoemission spectroscopy experiment and the calculation. Our work highlights that charge transfer, zone folding of graphene bands and the covalent bonding between C and Cs atoms are at the origin of the flat energy band formation. The presented approach is an alternative route for obtaining flat band materials to twisting bilayer graphene which yields thermodynamically stable flat band materials in large areas.

arXiv comment22 pages, 4 Figures

References in corpus (33)

• The electronic properties of graphene
• Magic-angle graphene superlattices: a new platform for unconventional superconductivity
• Raman spectroscopy as a versatile tool for studying the properties of graphene
• Moire bands in twisted double-layer graphene
• Topological nodal line semimetals with and without spin-orbital coupling
• Chiral superconductivity from repulsive interactions in doped graphene
• Mayavi: a package for 3D visualization of scientific data
• Non-adiabatic Kohn-anomaly in a doped graphene monolayer
• Strength of effective Coulomb interactions in graphene and graphite
• Artificial flat band systems: from lattice models to experiments
• High-temperature surface superconductivity in topological flat-band systems
• Experimental realization and characterization of an electronic Lieb lattice
• Seeing many-body effects in single- and few-layer graphene: Observation of two-dimensional saddle-point excitons
• Topological states in engineered atomic lattices
• Electronic structure of superconducting graphite intercalate compounds: The role of the interlayer state
• Direct Observation of Superconductivity in Calcium-Intercalated Bilayer Graphene by in situ Electrical Transport Measurements
• Density waves and Cooper pairing on the honeycomb lattice
• The mechanism of caesium intercalation of graphene
• Topological surface state under graphene for two-dimensional spintronics in air
• Superconductivity in Ca-doped graphene
• Excitonic Fano Resonance in Freestanding Graphene
• Electron-phonon coupling in potassium-doped graphene: Angle-resolved photoemission spectroscopy
• Breit-Wigner-Fano lineshapes in Raman spectra of graphene
• Tuning many-body interactions in graphene: The effects of doping on excitons and carrier lifetimes
• Disordered flat bands on the kagome lattice
• Flat Electronic Bands in Long Sequences of Rhombohedral-stacked Multilayer Graphene
• Experimental approval of the extended flat bands and gapped subbands in rhombohedral multilayer graphene
• Magnetic gap opening in rhombohedral-stacked multilayer graphene from first principles
• Superconductivity in graphite intercalation compounds
• Chemical potential asymmetry and quantum oscillations in insulators
• Narrow photoluminescence peak of epitaxial MoS${}_2$ on graphene/Ir(111)
• Comprehensive tunneling spectroscopy of quasi-freestanding MoS${}_2$ on graphene on Ir(111)
• Manifestation of nonlocal electron-electron interaction in graphene

Cited by in corpus (16)

• Visualization of the flat electronic band in twisted bilayer graphene near the magic angle twist
• Role of intercalated Cobalt in the electronic structure of Co${}_{1/3}$NbS${}_2$
• Can the "shadow" of graphene band clarify its flatness?
• Magnesium-intercalated graphene on SiC: highly n-doped air-stable bilayer graphene at extreme displacement fields
• Enhanced optical conductivity and many-body effects in strongly-driven photo-excited semi-metallic graphite
• Van Hove Singularity and Lifshitz Transition in Thickness-Controlled Li-Intercalated Graphene
• Optoelectronic Fingerprints of Interference between Different Charge Carriers in Graphene Superlattices and Analogies to Twisted Graphene Bilayers
• Electronic Structure and Kohn-Luttinger Superconductivity of Heavily-Doped Single-Layer Graphene
• Spin-dependent $\pi$${\pi }^{\ast }$ gap in graphene on a magnetic substrate
• Two-way twisting of a confined monolayer: orientational ordering within the van der Waals gap between graphene and its crystalline substrate
• Mass inversion at the Lifshitz transition in monolayer graphene by diffusive, high-density, on-chip, doping
• Band structure and optical response of Kekulé-modulated $\alpha -{\mathcal{T}}_3$ model
• Doping the spin-polarized Graphene minicone on Ni(111)
• Properties of bilayer graphene-like Si${}_2$C${}_{14}$ semiconductor using first-principle calculations
• Kerr and Faraday rotations in topological flat and dispersive band structures
• Using near-flat-band electrons for read-out of molecular spin qubit entangled states