Conductance gap and zero-bias conductance scaling in metallic carbon nanotubesJ. W. Ding1, 2 and D. Y. Xing1
1 National Laboratory of Solid State Microstructures Nanjing University - Nanjing 210093, PRC
2 Department of Physics, Xiangtan University Xiangtan 411105, Hunan, PRC
received 26 November 2004; accepted 28 February 2005
published online 16 March 2005
A new supercell approach is presented to the calculations for quantum conductance of single-wall carbon nanotubes as a function of tube length L, diameter d, and chirality. It is shown that there is a conductance gap (dip) in infinite (finite) metallic non-armchair nanotubes due to the curvature-induced energy gap, while it is absent in armchair tubes. This mediates a dispute in experiments. A scaling of is obtained for the zero-bias conductance where G0=2e2/h and depends only on the chiral angle. This behavior can be well understood by a proposed tunneling model.
61.48.+c - Fullerenes and fullerene-related materials.
71.20.Tx - Fullerenes and related materials; intercalation compounds.
© EDP Sciences 2005