The conductivity of within CNTs is a complex subject that involves the tube Chirality, defects, contamination and alignment among other things. These factors where discussed in a book chapter available at https://www.sciencedirect.com/science/article/pii/B9780128126677000185. Boronite has developed a process to make yarns from all single wall carbon nanotubes of predominately a metallic chirality. We term these yarns quantum wire, because of the nature of the conduction within these small structures. In general terms the growth process involves creating a catalyst of the desired size our reactor, using a fuel of a certain type and flooding this reactor with hydrogen. (Pat. Pending). The reason for doing this is that these tubes have a zero or near zero band gap which is very important at low temperatures. This process uses a scant amount of hydrogen and a very different kind of carbon source. In the manner analogous to the metallic tubes we have patented a process to synthesize all zig-zag tubes although this process has not been developed.
General Purpose Wiring:
Applications where this wiring has an advantage include very thin wiring resistant to breakage if it were copper, applications where the wiring has to be transparent to x-rays, wiring inside the body where corrosion is important. For some applications a simpler dual wall cnt wire would work.
Semiconductor nanowires can be used for transistors1. Transistors are used widely as fundamental building blocks in today's electronic circuits. The advantage has to do with the very high mobility of charge carries in short nanotubes and the extremely good conductivity in single nanotube devices so that heat buildup is minimal and electromigration is eliminated so switching speeds are high.
Metallic Quantum wires:
These were developed to promote a highly conductive material that can take high temperatures during extreme electron emission. The single wall quantum wires contain a distribution of single wall CNT bundles in which, all the tubes are the same length and within the bundle are well bonded together. Such bundles can have excellent properties. At low temperatures wires of this kind of tube should provide better behavior than comparable dual wall CNTs.
Dekker, Cees; Tans, Sander J.; Verschueren, Alwin R. M. (1998). "Room-temperature transistor based on a single carbon nanotube". Nature. 393 (6680): 49–52. Bibcode:1998Natur.393...49T. doi:10.1038/29954. Martel, R.; Schmidt, T.; Shea, H. R.; Hertel, T.; Avouris, Ph. (1998). "Single- and multi-wall carbon nanotube field-effect transistors" (PDF). Applied Physics Letters. 73 (17): 2447. Bibcode:1998ApPhL..73.2447M. doi:10.1063/1.122477.