TY - JOUR

T1 - Twisted Bilayer Graphene

T2 - Interlayer Configuration and Magnetotransport Signatures

AU - Rode, Johannes C.

AU - Smirnov, Dmitri

AU - Belke, Christopher

AU - Schmidt, Hennrik

AU - Haug, Rolf J.

N1 - Funding Information: This work was supported by the priority program SPP 1459 “Graphene” of the DFG. Funding Information: This work was supported by the priority program SPP 1459 ?Graphene? of the DFG. J. C. Rode acknowledges support from the Hannover School for Nanotechnology. We thank Patrick Barthold and Thomas L?dtke for valuable input at early stages of the project as well as Hadar Steinberg and Peter Behrens for helpful insight and discussions. The authors have declared no conflict of interest.

PY - 2017/11/9

Y1 - 2017/11/9

N2 - Twisted Bilayer Graphene may be viewed as very first representative of the now booming class of artificially layered 2D materials. Consisting of two sheets from the same structure and atomic composition, its decisive degree of freedom lies in the rotation between crystallographic axes in the individual graphene monolayers. Geometrical consideration finds angle-dependent Moiré patterns as well as commensurate superlattices of opposite sublattice exchange symmetry. Beyond the approach of rigidly interposed lattices, this review takes focus on the evolving topic of lattice corrugation and distortion in response to spatially varying lattice registry. The experimental approach to twisted bilayers requires a basic control over preparation techniques; important methods are summarized and extended on in the case of bilayers folded from monolayer graphene via AFM nanomachining. Central morphological parameters to the twisted bilayer, rotational mismatch and interlayer separation are studied in a broader base of samples. Finally, experimental evidence for a number of theoretically predicted, controversial electronic scenarios are reviewed; magnetotransport signatures are discussed in terms of Fermi velocity, van Hove singularities and Berry phase and assessed with respect to the underlying experimental conditions, thereby referring back to the initially considered variations in relaxed lattice structure.

AB - Twisted Bilayer Graphene may be viewed as very first representative of the now booming class of artificially layered 2D materials. Consisting of two sheets from the same structure and atomic composition, its decisive degree of freedom lies in the rotation between crystallographic axes in the individual graphene monolayers. Geometrical consideration finds angle-dependent Moiré patterns as well as commensurate superlattices of opposite sublattice exchange symmetry. Beyond the approach of rigidly interposed lattices, this review takes focus on the evolving topic of lattice corrugation and distortion in response to spatially varying lattice registry. The experimental approach to twisted bilayers requires a basic control over preparation techniques; important methods are summarized and extended on in the case of bilayers folded from monolayer graphene via AFM nanomachining. Central morphological parameters to the twisted bilayer, rotational mismatch and interlayer separation are studied in a broader base of samples. Finally, experimental evidence for a number of theoretically predicted, controversial electronic scenarios are reviewed; magnetotransport signatures are discussed in terms of Fermi velocity, van Hove singularities and Berry phase and assessed with respect to the underlying experimental conditions, thereby referring back to the initially considered variations in relaxed lattice structure.

KW - Atomic Force Microscope

KW - Graphene

KW - Magnetotransport

KW - Twisted Bilayer

UR - http://www.scopus.com/inward/record.url?scp=85026489916&partnerID=8YFLogxK

U2 - 10.1002/andp.201700025

DO - 10.1002/andp.201700025

M3 - Article

AN - SCOPUS:85026489916

VL - 529

JO - Annalen der Physik

JF - Annalen der Physik

SN - 0003-3804

IS - 11

M1 - 1700025

ER -