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

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 Added by Massimo Rontani
 Publication date 2013
  fields Physics
and research's language is English




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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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