Three-terminal scanning tunneling spectroscopy of suspended carbon   nanotubes
  We have performed low-temperature scanning tunneling spectroscopy measurements on suspended single-wall carbon nanotubes with a gate electrode allowing three-terminal spectroscopy measurements. These measurements show well-defined Coulomb diamonds as well as side peaks from phonon-assisted tunneling. The side peaks have the same gate voltage dependence as the main Coulomb peaks, directly proving that they are excitations of these states. 
B.J. LeRoy, J. Kong, V.K. Pahilwani, C. Dekker, S.G. Lemay