Carbon nanotube apparatus, and methods of carbon nanotube modification, include carbon nanotubes having locally modified properties with the positioning of the modifications being controlled. More specifically, the positioning of nanotubes on a substrate with a deposited substance, and partially vaporizing part of the deposited substance etches the nanotubes. The modifications of the carbon nanotubes determine the electrical properties of the apparatus and applications such as a transistor or Shockley diode. Other applications of the above mentioned apparatus include a nanolaboratory that assists in study of merged quantum states between nanosystems and a macroscopic host system.