title: Electronic transport spectroscopy of carbon nanotubes in a magnetic field.
abstract: We report magnetic field spectroscopy measurements in carbon nanotube quantum dots exhibiting fourfold shell structure in the energy level spectrum. The magnetic field induces a large splitting between the two orbital states of each shell, demonstrating their opposite magnetic moment and determining transitions in the spin and orbital configuration of the quantum dot ground state. We use inelastic cotunneling spectroscopy to accurately resolve the spin and orbital contributions to the magnetic moment. A small coupling is found between orbitals with opposite magnetic moment leading to anticrossing behavior at zero field.
authors.affiliation: Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
authors.forename: P
authors.initials: P
authors.lastname: Jarillo-Herrero
authors.forename: J
authors.initials: J
authors.lastname: Kong
authors.forename: H S J
authors.initials: HS
authors.lastname: van der Zant
authors.forename: C
authors.initials: C
authors.lastname: Dekker
authors.forename: L P
authors.initials: LP
authors.lastname: Kouwenhoven
authors.forename: S
authors.initials: S
authors.lastname: De Franceschi