We investigate the coupling between individual tubes in a rope of single-wall carbon nanotubes using four probe resistance measurements. By introducing defects through the controlled sputtering of the rope we generate a strong non-monotonic temperature dependence of the four terminal resistance. This behavior reflects the interplay between localization in the intentionally damaged tubes and coupling to undamaged tubes in the same rope. Using a simple model we obtain the coherence length and the coupling resistance. The coupling mechanism is argued to involve direct tunneling between tubes.
@article{arxiv.cond-mat/0003423,
title = {Intertube coupling in ropes of single-wall carbon nanotubes},
author = {H. Stahl and J. Appenzeller and R. Martel and Ph. Avouris and B. Lengeler},
journal= {arXiv preprint arXiv:cond-mat/0003423},
year = {2009}
}