Ambipolar single electron transistors using side-contacted single-walled carbon nanotubes

We report on single electron transistor (SET) operation in single-walled carbon nanotubes (SWNTs) to estimate the length of ballistic conduction in laser-synthesized SWNTs. The devices were fabricated by an alternating current-aligned method and the SWNTs were side-contacted to the electrodes. At 5 K, Coulomb oscillation and Coulomb diamonds were observed and the Coulomb island length, i.e., the ballistic conduction length, was calculated to be about 200–300 nm. To the best of our knowledge, this is the first report of an SET using an aligned-fabrication methodology and a solution process.