Multiple-Valued Computing Using Field Emission – Based Carbon Nanotube Controlled Switching

A new carbon nanotube (CNT) based controlled switch is introduced. The new CNT device is a field emission – based device that uses field electron emission from the CNT to implement the functionality of controlled switching. To implement the field emission CNT controlled switch, four field emission CNTs that have single carbon nanotubes as the emitters were tested; two with single-walled CNT and two with multi-walled CNT. A tube with a tungsten tip was also used for comparison. The Fowler-Nordheim analysis of the DC currentvoltage data provided reasonable values for the local fields at the emitters and the sizes of the emitters. It is also shown within the new implementation of the controlled switch that squarewave pulses from a single laser diode with 20 mW power and 658 nm wavelength which is focused on each emitter increased the emitted current by 5.2% with the CNT and 0.19% with the compared tungsten tip. The extension of the new device from the two-valued to the general m-valued case is introduced, and the implementation of multiple-valued Galois circuits and systems utilizing the new CNT field emission – based device is also shown. Since the controlled switch is a basic block in the design of modern digital systems, the new CNT device can have a wide range of applications in a wide variety of nano circuits. Index Terms Carbon Nanotubes, Controlled Switching, Fault Tolerance, Fowler-Nordheim Analysis, Field Emission, Multiple-Valued Computing, Nanotechnology.