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arXiv · 1311.6271

Electron dynamics in graphene with gate-defined quantum dots

A. Pieper·R. L. Heinisch·H. Fehske
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Abstract

We use numerically exact Chebyshev expansion and kernel polynomial methods to study transport through circular graphene quantum dots in the framework of a tight-binding honeycomb lattice model. Our focus lies on the regime where individual modes of the electrostatically defined dot dominate the charge carrier dynamics. In particular, we discuss the scattering of an injected Dirac electron wave packet for a single quantum dot, electron confinement in the dot, the optical excitation of dot-bound modes, and the propagation of an electronic excitation along a linear array of dots.

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A. Pieper, R. L. Heinisch, H. Fehske. 2013-12-16. Electron dynamics in graphene with gate-defined quantum dots. https://doi.org/10.1209/0295-5075%2F104%2F47010

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