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arXiv · 1301.3354

Snake states in graphene quantum dots in the presence of a p-n junction

M. Zarenia·J. M. Pereira Jr·F. M. Peeters·G. A. Farias
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Abstract

We investigate the magnetic interface states of graphene quantum dots that contain p-n junctions. Within a tight-binding approach, we consider rectangular quantum dots in the presence of a perpendicular magnetic field containing p-n, as well as p-n-p and n-p-n junctions. The results show the interplay between the edge states associated with the zigzag terminations of the sample and the snake states that arise at the p-n junction, due to the overlap between electron and hole states at the potential interface. Remarkable localized states are found at the crossing of the p-n junction with the zigzag edge having a dumb-bell shaped electron distribution. The results are presented as function of the junction parameters and the applied magnetic flux.

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M. Zarenia, J. M. Pereira Jr, F. M. Peeters, G. A. Farias. 2013-01-15. Snake states in graphene quantum dots in the presence of a p-n junction. https://doi.org/10.1103/physrevb.87.035426

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