Angle-dependent electron confinement in graphene moire superlattices
Por:
Sanchez-Ochoa, Francisco, Botello-Mendez, Andres R., Noguez, Cecilia
Publicada:
17 ago 2021
Resumen:
In graphene moire superlattices, electronic interactions between layers
are mostly hidden as band structures get crowded because of folding,
making their interpretation cumbersome. Here, the evolution of the
electronic band structure as a function of the interlayer rotation angle
is studied using density functional theory followed by unfolding bands
and then comparing them with their corresponding individual components.
We observe interactions in regions not theoretically elucidated so far,
where for small interlayer angles, gaps turn into discretelike states
that are evenly spaced in energy. We find that V-pp sigma attractive
interactions between out-of-plane orbitals from different layers are
responsible for the discretization. Furthermore, when the interlayer
angle becomes small, these discrete, evenly spaced states have energy
differences comparable to graphene phonons. Thus they might be relevant
to explain electron-phonon-assisted effects, which have been
experimentally observed in graphene moire superlattices.
Filiaciones:
Sanchez-Ochoa, Francisco:
Noguez, C (Corresponding Author), Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Mexico City 01000, DF, Mexico. Sanchez-Ochoa, Francisco
Noguez, Cecilia:
Noguez, C (Corresponding Author), Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Mexico City 01000, DF, Mexico. Sanchez-Ochoa, Francisco
Open Access
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