Interplay between Kondo physics and spin-orbit coupling in carbon nanotube quantum dots
Abstract
We investigate the influence of spin-orbit coupling on the Kondo effects in carbon nanotube quantum dots, using the numerical renormalization group technique. A sufficiently large spin-orbit coupling is shown to destroy the SU(4) Kondo effects at zero magnetic field, leaving only two SU(2) Kondo effects in the one- and three-electron Coulomb blockade valleys. On applying a finite magnetic field, two additional, spin-orbit induced SU(2) Kondo effects arise in the three- and two-electron valleys. Using physically realistic model parameters, we calculate the differential conductance over a range of gate voltages, temperatures and fields. The results agree well with measurements from two different experimental devices in the literature, and explain a number of observations that are not described within the standard framework of the SU(4) Anderson impurity model.
Cite
@article{arxiv.0911.2886,
title = {Interplay between Kondo physics and spin-orbit coupling in carbon nanotube quantum dots},
author = {Martin R. Galpin and Frederic W. Jayatilaka and David E. Logan and Frithjof B. Anders},
journal= {arXiv preprint arXiv:0911.2886},
year = {2010}
}
Comments
15 pages, 11 figures