At Delft, we obtained the first transport results on individual single-walled carbon nanotubes. These were grown by the Smalley group at Rice University. We demonstrated that it is possible to deposit individual nanotube molecules on nanofabricated electrodes. At low temperatures step-like current-voltage characteristics are obtained that indicate single-electron transport with Coulomb blockade and resonant tunneling through single molecular orbitals. In Coulomb blockade, transport is blocked at low bias since the capacitance of the nanotube is so small that adding a single electron requires a charging energy that is larger than the thermal energy. The zero-bias conductance can be restored by tuning the electrostatic potential of the tube with a gate voltage. Quite remarkably, the nanotubes appear to behave as coherent quantum wires. Electron-transport spectroscopy was carried out at mK temperatures. The density of states of the molecule appears to consist of well-separated discrete electron states. Their ~0.4 meV energy separation corresponds to estimates for a one-dimensional
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P.D. Jarillo-Herrero, J.Kong, H.S.J. van der Zant, C. Dekker, L.P. Kouwenhoven, and S. De Franceschi Tunable orbital pseudospin and multi-level Kondo effect in carbon nanotubes In H Kuzmany, J Fink, M Mehring, & S Roth (Eds.), Properties of Novel Nanostructures Vol. 786. Aip conference proceedings (pp. 482-489). 2005, Kirchberg, Austria: AIP B.J. LeRoy, J. Kong, V.K. Pahilwani, C. Dekker, and S.G. Lemay Three-terminal scanning tunneling spectroscopy of suspended carbon nanotubes Phys. Rev.