arXiv subjects

P. Mallet

Publications and source records attributed to P. Mallet.

20 records · Page 2Linked to original sources

arXiv2008

Quasiparticle Chirality in Epitaxial Graphene Probed at the Nanometer Scale

Graphene exhibits unconventional two-dimensional electronic properties resulting from the symmetry of its quasiparticles, which leads to the concepts of pseudospin and electronic chirality. Here we report that scanning tunneling microscopy can be used to probe these unique symmetry properties at the nanometer scale. They are reflected in the quantum interference pattern resulting from elastic scattering off impurities, and they can be directly read from its fast Fourier transform. Our data, complemented by theoretical calculations, demonstrate that the pseudospin and the electronic chirality in epitaxial graphene on SiC(0001) correspond to the ones predicted for ideal graphene.

cond-mat.mtrl-sci↗

arXiv2007

Ripples in epitaxial graphene

Graphene outstanding properties directly come from its pecular electronic structure and thus from the honeycomb lattice symmetry. The way interaction with the substrate impact this lattice is of primary importance. This is peculiarly true for epitaxial graphene because of the SiC substrate. The advantage of this system that produces macroscopic samples in registry with a substrate could turn to a major drawback if the graphene lattice reveals to be strongly distorted. Extensive ab initio calculations supported by Scanning Tunneling Microscopy experiments, demonstrate here that the substrate indeed induces a strong nanostructuration of the interface carbon layer. It propagates to the above C layer where it generates incommensurate ripples in the honeycomb lattice.

cond-mat.mtrl-sci↗