Graphene is just one monolayer of graphite, a hexagonal arrangement of carbon atoms, which has a linear dispersion relation around the Fermi energy. Thus, its carriers can be described as massless Dirac fermions, allowing the study of relativistic dynamics in a typical solid-state material.
Graphene is one of the hottest topics in condensed matter physics due to its remarkable properties (high electron mobility, flexibility, long electron spin lifetime, potential for chemical functionality…) which make it a promising material for multiple applications.
Properties of carbon allotropes depend strongly on their dimensionality, geometry and topology. Cutting graphene into nanoribbons or rolling up it into nanotubes alters the electronic properties of graphene. Carbon nanotubes and graphene nanoribbons can be metallic or semiconducting depending on their geometry, which has a fundamental role in other physical properties.
The transport and optical properties of isolated graphene layers are also strongly affected when they are piled up one on top of the other forming multilayers graphene structures. Even the properties of bilayer graphene depend on the atomic stacking between the layers.
Graphene is isolated from graphite by mechanical exfoliation and similar techniques used for obtaining graphene layers have been also applied to obtain other two-dimensional crystal structures as hexagonal Boron Nitride (hBN) or transition metal dichalcogenides. Once isolated, atomic layers of diﬀerent 2D crystals can be reassembled layer by layer to create heterostructures with the designed electrical properties. This has opened a new field named graphene based Van der Walls heterostructures.
Our work on carbon based structures has been focused on the electric and transport properties of graphene, nanotubes and nanoribbons. We have also studied properties of bilayer graphene with different atomic stacking.
Dielectric screening and plasmons in AA-stacked bilayer graphene
Rafael Roldán and Luis Brey
Phys. Rev. B 88, 115420 (2013)
Interplay between symmetry and spin-orbit coupling on graphene nanoribbons
Hernán Santos, M. C. Muñoz, M. P. López-Sancho, and Leonor Chico
Phys. Rev. B 87, 235402 (2013)
Grain boundaries with octagonal defects in graphene nanoribbons and nanotubes
M. Pelc, L. Chico, A. Ayuela, and W. Jaskólski
Phys. Rev. B 87, 165427 (2013)
Electronic properties of twisted trilayer graphene
E. Suárez Morell, M. Pacheco, L. Chico, and L. Brey
Phys. Rev. B 87, 125414 (2013)
Gapped phase in AA-stacked bilayer graphene
L. Brey and H. A. Fertig
Phys. Rev. B 87, 115411 (2013)