Abstract
The quantum-mechanical orbitals in carbon nanotube quantum dots are doubly degenerate over a large number of states. We argue that this experimental observation indicates that electrons are reflected without mode mixing at the nanotube-metal contacts. Two electrons occupying a pair of degenerate orbitals (“shell”) are found to form a triplet state starting from zero magnetic field. Finally, we observe unexpected low-energy excitations at complete filling of a four-electron shell.
- Received 18 September 2005
DOI:https://doi.org/10.1103/PhysRevB.74.155431
©2006 American Physical Society