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arXiv · 0805.0454

Tuning of energy levels and optical properties of graphene quantum dots

Z. Z. Zhang·Kai Chang·F. M. Peeters
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Abstract

We investigate theoretically the magnetic levels and optical properties of zigzag- and armchair-edged hexagonal graphene quantum dots (GQDs) utilizing the tight-binding method. A new bound edge state at zero energy appears for the zigzag GQDs in the absence of a magnetic field. The magnetic levels of GQDs exhibit a Hofstadter-butterfly spectrum and approach the Landau levels of two-dimensional graphene as the magnetic field increases. The optical properties are tuned by the size, the type of the edge, and the external magnetic field.

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Z. Z. Zhang, Kai Chang, F. M. Peeters. 2008-05-05. Tuning of energy levels and optical properties of graphene quantum dots. https://doi.org/10.1103/physrevb.77.235411

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