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NanoARPES of twisted bilayer graphene on SiC: absence of velocity renormalization for small angles.

ABSTRACT: The structural and electronic properties of twisted bilayer graphene (TBG) on SiC(000) grown by Si flux-assisted molecular beam epitaxy were investigated using scanning tunneling microscopy (STM) and angle-resolved photoelectron spectroscopy with nanometric spatial resolution. STM images revealed a wide distribution of twist angles between the two graphene layers. The electronic structure recorded in single TBG grains showed two closely-spaced Dirac π bands associated to the two stacked layers with respective twist angles in the range 1-3°. The renormalization of velocity predicted in previous theoretical calculations for small twist angles was not observed.

SUBMITTER: Razado-Colambo I

PROVIDER: S-EPMC4893698 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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NanoARPES of twisted bilayer graphene on SiC: absence of velocity renormalization for small angles.

Razado-Colambo I I Avila J J Nys J-P JP Chen C C Wallart X X Asensio M-C MC Vignaud D D

Scientific reports 20160606

The structural and electronic properties of twisted bilayer graphene (TBG) on SiC(000) grown by Si flux-assisted molecular beam epitaxy were investigated using scanning tunneling microscopy (STM) and angle-resolved photoelectron spectroscopy with nanometric spatial resolution. STM images revealed a wide distribution of twist angles between the two graphene layers. The electronic structure recorded in single TBG grains showed two closely-spaced Dirac π bands associated to the two stacked layers w ...[more]

PMID: 27264791

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