Realistic Nanotube-Metal Contact Configuration for Molecular Electronics Applications

A realistic single-wall carbon nanotube (SWCN)-metal contact configuration is obtained using a tight-binding molecular dynamics method incorporating full consideration of s, p, and d basis sets for carbon and metal atoms. The full structural relaxation of the combined SWCN and metal system is found to be essential for realistic characterization of conductivity. More importantly, convergence with respect to the number of the metal lead (ML) atoms in contact with the SWCN is found to be even more critical. Our results indicate that, in order to maximize device efficiency, one needs to use ML-SWCN systems with a minimal ML-SWCN contact-width to SWCN-length ratio.