Evidence for Superlattice Dirac Points and Space-dependent Fermi Velocity in Corrugated Graphene Monolayer

Abstract

Recent studies show that periodic potentials can generate superlattice Dirac points at energies in graphene (is the Fermi velocity of graphene and G is the reciprocal superlattice vector). Here, we perform scanning tunneling microscopy and spectroscopy studies of a corrugated graphene monolayer on Rh foil. We show that the quasi-periodic ripples of nanometer wavelength in the corrugated graphene give rise to weak one-dimensional (1D) electronic potentials and thereby lead to the emergence of the superlattice Dirac points. The position of the superlattice Dirac point is space-dependent and shows a wide distribution of values. We demonstrated that the space-dependent superlattice Dirac points is closely related to the space-dependent Fermi velocity, which may arise from the effect of the local strain and the strong electron-electron interaction in the corrugated graphene.

4figures

References in corpus (19)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• Chiral tunneling and the Klein paradox in graphene
• Quantum interference and Klein tunneling in graphene heterojunctions
• Emergence of Superlattice Dirac Points in Graphene on Hexagonal Boron Nitride
• Anisotropic behaviors of massless Dirac fermions in graphene under periodic potential
• Periodically rippled graphene: growth and spatially resolved electronic structure
• New Generation of Massless Dirac Fermions in Graphene under External Periodic Potentials
• Midgap states and charge inhomogeneities in corrugated graphene
• Electronic properties of graphene: a perspective from scanning tunneling microscopy and magneto-transport
• Gauge field induced by ripples in graphene
• Breakdown of continuum mechanics for nanometer-wavelength rippling of graphene
• Chirality and Correlations in Graphene
• Quasiparticle Chirality in Epitaxial Graphene Probed at the Nanometer Scale
• Landau Levels and Quantum Hall Effect in Graphene Superlattices
• Electronic superlattices in corrugated graphene
• Transport in superlattices on single layer graphene
• Effective Magnetic Fields in Graphene Superlattices
• Enhanced Intervalley Scattering of Twisted Bilayer Graphene by Periodic AB Stacked Atoms

Cited by in corpus (3)

• The Coexistence of van Hove Singularities and Superlattice Dirac Points in a Slightly Twisted Graphene Bilayer
• Electronic structure of a graphene superlattice with a modulated Fermi velocity
• Electronic structure of a graphene superlattice with massive Dirac fermions