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arXiv · 0711.4446

Quasi-bound states of quantum dots in single and bilayer graphene

A. Matulis·F. M. Peeters
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Abstract

Dirac fermions interacting with a cylindrically symmetric quantum dot potential created in single and bilayer graphene are not confined but form quasi-bound states. The broadening of these quasi-bound states (i. e. the inverse of their lifetimes) decreases (increases) with the orbital momentum of the electron in the case of graphene (bilayer). Quasi-bound states with energy below (above) the barrier height are dominantly electron(hole)-like. A remarkable decrease of the energy level broadening is predicted for electron energies close to the barrier height, which are a consequence of the total internal reflection of the electronic wave at the dot edge.

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A. Matulis, F. M. Peeters. 2007-11-28. Quasi-bound states of quantum dots in single and bilayer graphene. https://doi.org/10.1103/physrevb.77.115423

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