Carbon nanotubes as building blocks of quantum dots

Quantum dots have been fabricated with single-wall carbon nanotubes (SWCNTs), and their transport properties have been measured at low temperatures. The single-electron transport measurements revealed the artificial atom characteristics with a shell structure and the Zeeman splitting of single particle states. They have been observed with the metallic SWCNT that includes many electrons, in striking contrast to the case of semiconductor artificial atoms that have a few electrons. The unique features in the SWCNT artificial atom are discussed in terms of the energy scales associated with the quantum dot.