Nonlinear conductance reveals positions of carbon atoms in metallic single-wall carbon nanotubes

Iran University of Science and Technology Department of Physics Narmak, 16345 Tehran Iran
Physics of Condensed Matter (Impact Factor: 1.28). 01/2009; 72(1):89-95. DOI: 10.1140/epjb/e2009-00303-4

ABSTRACT Nonlinear quantum conductance in finite metallic single-wall carbon nanotubes due to presence of a single defect has been
studied theoretically using π-orbital tight-binding model. The correction to the conductance induced by defects is sensitively
dependent on wavefunction amplitudes of contributing electronic states. It has been shown that by calculating this correction
to the first order, we can delineate the position of carbon atoms on tubular surface. It can also be used to specify the SWCNT
at hand and its level spacing.

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