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arXiv · 0801.0160

Chaotic Dirac billiard in graphene quantum dots

L. A. Ponomarenko·F. Schedin·M. I. Katsnelson·R. Yang·E. H. Hill·K. S. Novoselov·A. K. Geim
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Abstract

We report on transport characteristics of quantum dot devices etched entirely in graphene. At large sizes, they behave as conventional single-electron transistors, exhibiting periodic Coulomb blockade peaks. For quantum dots smaller than 100 nm, the peaks become strongly non-periodic indicating a major contribution of quantum confinement. Random peak spacing and its statistics are well described by the theory of chaotic neutrino (Dirac) billiards. Short constrictions of only a few nm in width remain conductive and reveal a confinement gap of up to 0.5eV, which demonstrates the in-principle possibility of molecular-scale electronics based on graphene.

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L. A. Ponomarenko, F. Schedin, M. I. Katsnelson, R. Yang, E. H. Hill, K. S. Novoselov, A. K. Geim. 2007-12-30. Chaotic Dirac billiard in graphene quantum dots. https://doi.org/10.1126/science.1154663

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