Local density of states and Friedel oscillations in graphene

Local density of states and scanning tunneling currents in graphene

We present exact analytical calculations of scanning tunneling currents in locally disordered graphene using a multimode description of the microscope tip. Analytical expressions for the local density of states (LDOS) are given for energies beyond the Dirac cone approximation. We show that the LDOS at the A and B sublattices of graphene are out of phase by π implying that the averaged LDOS, as ...

Long-wavelength local density of states oscillations near graphene step edges.

Using scanning tunneling microscopy and spectroscopy, we have studied the local density of states (LDOS) of graphene over step edges in boron nitride. Long-wavelength oscillations in the LDOS are observed with maxima parallel to the step edge. Their wavelength and amplitude are controlled by the energy of the quasiparticles allowing a direct probe of the graphene dispersion relation. We also ob...

Friedel oscillations at the surfaces of rhombohedral N-layer graphene

Friedel oscillations, impurity scattering, and temperature dependence of resistivity in graphene.

We show that Friedel oscillations (FO) in grapehene are strongly affected by the chirality of electrons in this material. In particular, the FO of the charge density around an impurity show a faster (deltarho approximately r;{-3}) decay than in conventional 2D electron systems and do not contribute to a linear temperature-dependent correction to the resistivity. In contrast, the FO of the excha...

The Local Density of States in Monolayer and Bilayer Graphene in the Presence of an Impurity

We analyze the effect of a single localized impurity on the local density of states in monoand bilayer undoped graphene. We show that for monolayer graphene the Friedel oscillations generated by intranodal scattering of quasiparticles obey an inverse-square law, while those generated by internodal scattering obey an inverse law. Unlike the former, the latter oscillations may break rotational sy...