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

ArticleinPhysics of Condensed Matter 72(1):89-95 · November 2009with6 Reads
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.
  • [Show abstract] [Hide abstract] ABSTRACT: By using a simple method, the effects of a substitutional magnetic impurity on the conductance of metallic single-wall carbon nanotubes, lying between two spin-polarized electron reservoirs, are studied. It is demonstrated how the differential conductance depends sensitively on the radius and length of nanotube as well as the position of impurity. It is shown that magnetic impurity produces more effect for the spin-polarized current between the antiparallel reservoirs than the parallel ones. (c) 2010 Elsevier B.V. All rights reserved.
    Full-text · Article · Nov 2010
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