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arXiv · 1306.3502

Inter-valley scattering induced by Coulomb interaction and disorder in carbon-nanotube quantum dots

Andrea Secchi·Massimo Rontani
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Abstract

We develop a theory of inter-valley Coulomb scattering in semiconducting carbon-nanotube quantum dots, taking into account the effects of curvature and chirality. Starting from the effective-mass description of single-particle states, we study the two-electron system by fully including Coulomb interaction, spin-orbit coupling, and short-range disorder. We find that the energy level splittings associated with inter-valley scattering are nearly independent of the chiral angle and, while smaller than those due to spin-orbit interaction, large enough to be measurable.

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Andrea Secchi, Massimo Rontani. 2013-06-14. Inter-valley scattering induced by Coulomb interaction and disorder in carbon-nanotube quantum dots. https://doi.org/10.1103/physrevb.88.125403

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