English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Pseudospin, an additional degree of freedom related to the honeycombstructure of graphene, is responsible of many of the outstanding electronicproperties found in this material. This article provides a clear understandingof how such pseudospin impacts the quasiparticle interferences of monolayer(ML) and bilayer (BL) graphene measured by low temperature scanning tunnelingmicroscopy and spectroscopy. We have used this technique to map, with very highenergy and space resolution, the spatial modulations of the local density ofstates of ML and BL graphene epitaxialy grown on SiC(0001), in presence ofnative disorder. We perform a Fourier transform analysis of such modulationsincluding wavevectors up to unit-vectors of the reciprocal lattice. Our datademonstrate that the quasiparticle interferences associated to some particularscattering processes are suppressed in ML graphene, but not in BL graphene.Most importantly, interferences with 2qF wavevector associated to intravalleybackscattering are not measured in ML graphene, even on the images with highestresolution. In order to clarify the role of the pseudospin on the quasiparticleinterferences, we use a simple model which nicely captures the main featuresobserved on our data. The model unambiguously shows that graphene's pseudospinis responsible for such suppression of quasiparticle interferences features inML graphene, in particular for those with 2qF wavevector. It also confirmsscanning tunneling microscopy as a unique technique to probe the pseudospin ingraphene samples in real space with nanometer precision. Finally, we show thatsuch observations are robust with energy and obtain with great accuracy thedispersion of the \pi-bands for both ML and BL graphene in the vicinity of theFermi level, extracting their main tight binding parameters.

Role of pseudospin in quasiparticle interferences in epitaxial graphene probed by high-resolution scanning tunneling microscopy