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Register a new userConditional electron confinement in graphene via smooth magnetic fields
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In this article we discuss confinement of electrons in graphene via smooth magnetic fields which are finite everywhere on the plane. We shall consider two types of magnetic fields leading to systems which are conditionally exactly solvable and quasi exactly solvable. The bound state energies and wave functions in both cases have been found exactly.
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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 to their corresponding individual components. We observe interactions at regions not theoretically elucidated so far, where for small interlayer angles, gaps turn into discrete-like states that are evenly spaced in energy. We find that $V_{ppsigma}$ 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.
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