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arXiv · 0903.3590

Graphene armchair nanoribbon single-electron transistors: The peculiar influence of end states

Sonja Koller·Leonhard Mayrhofer·Milena Grifoni
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Abstract

We present a microscopic theory for interacting graphene armchair nanoribbon quantum dots. Long range interaction processes are responsible for Coulomb blockade and spin-charge separation. Short range ones, arising from the underlying honeycomb lattice of graphene, smear the spin-charge separation and induce exchange correlations between bulk electrons - delocalized on the ribbon - and single electrons localized at the two ends. As a consequence, entangled end-bulk states where the bulk spin is no longer a conserved quantity occur. Entanglement's signature is the occurrence of negative differential conductance effects in a fully symmetric set-up due to symmetry-forbidden transitions.

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Sonja Koller, Leonhard Mayrhofer, Milena Grifoni. 2009-03-20. Graphene armchair nanoribbon single-electron transistors: The peculiar influence of end states. https://doi.org/10.1209/0295-5075/88/57001

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