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arXiv · 0803.2465

Coupled quantum wires

D. Makogon·N. de Jeu·C. Morais Smith
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Abstract

We study a set of crossed 1D systems, which are coupled with each other via tunnelling at the crossings. We begin with the simplest case with no electron-electron interactions and find that besides the expected level splitting, bound states can emerge. Next, we include an external potential and electron-electron interactions, which are treated within the Hartree approximation. Then, we write down a formal general solution to the problem, giving additional details for the case of a symmetric external potential. Concentrating on the case of a single crossing, we were able to explain recent experinents on crossed metallic and semiconducting nanotubes [J. W. Janssen, S. G. Lemay, L. P. Kouwenhoven, and C. Dekker, Phys. Rev. B 65, 115423 (2002)], which showed the presence of localized states in the region of crossing.

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D. Makogon, N. de Jeu, C. Morais Smith. 2008-03-17. Coupled quantum wires. https://doi.org/10.1103/physrevb.78.115123

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