title: Interplay of the Kondo effect and strong spin-orbit coupling in multihole ultraclean carbon nanotubes.
abstract: We report on cotunneling spectroscopy magnetoconductance measurements of multihole ultraclean carbon nanotube quantum dots in the SU(4) Kondo regime with strong spin-orbit coupling. Successive shells show a gradual weakening of the Kondo effect with respect to the spin-orbital splittings, leading to an evolution from SU(4) to SU(2) symmetry with a suppressed conductance at half-shell filling. The extracted energy level spectrum, overall consistent with negligible disorder in the nanotube, shows in the half filled case large renormalizations due to Coulombian effects.
authors.affiliation: Institut Néel, CNRS and Université Grenoble Alpes, BP 166, F-38042 Grenoble, France.
authors.forename: J P
authors.initials: JP
authors.lastname: Cleuziou
authors.forename: N V
authors.initials: NV
authors.lastname: N'Guyen
authors.forename: S
authors.initials: S
authors.lastname: Florens
authors.forename: W
authors.initials: W
authors.lastname: Wernsdorfer