Transport Properties Of Nanotubes Research Articles

Oscillations in the spatial distribution of current in nanotubes and nanowires

The electronic transport process in nanotubes and nanowires along their axes is investigated. Attention is focused on the distribution of current within the structure, which is found to exhibit well-defined oscillations in the radial direction. The case in which an external magnetic field parallel to the nanowire or nanotube axis is applied to the system is also considered. In all cases, the origin of the oscillations and corresponding periods are identified. Effects of this behavior on the transport properties of nanotubes and nanowires are noted.

Electronic Transport Properties of Single-Walled Zigzag Silicon Carbide Nanotubes with Antisite Defects

The electronic transport properties are the basis for investigations on silicon carbide nanotube (SiCNT), which are suitable to develop novel nanometer electronic devices. The electronic transport properties of Single-Walled (8, 0) SiCNTs with antisite defects are investigated with the method combined Non-Equilibrium Green’s function with density functional theory. Results show that the similarity on electronic transport properties of the nanotube with different defects is high. Under a bias value greater than 1.0 V, a nearly exponential relationship between the bias and the current is achieved, which originates from more orbital participating in its transport properties caused by the increase of the bias.

Electronic and transport properties of nanotubes

This article reviews the electronic and transport properties of carbon nanotubes. The focus is mainly theoretical, but when appropriate the relation with experimental results is mentioned. While simple band-folding arguments will be invoked to rationalize how the metallic or semiconducting character of nanotubes is inferred from their topological structure, more sophisticated tight-binding and ab initio treatments will be introduced to discuss more subtle physical effects, such as those induced by curvature, tube-tube interactions, or topological defects. The same approach will be followed for transport properties. The fundamental aspects of conduction regimes and transport length scales will be presented using simple models of disorder, with the derivation of a few analytic results concerning specific situations of short- and long-range static perturbations. Further, the latest developments in semiempirical or ab initio simulations aimed at exploring the effect of realistic static scatterers (chemical impurities, adsorbed molecules, etc.) or inelastic electron-phonon interactions will be emphasized. Finally, specific issues, going beyond the noninteracting electron model, will be addressed, including excitonic effects in optical experiments, the Coulomb-blockade regime, and the Luttinger liquid, charge density waves, or superconducting transition.

First-principles calculations of contact effect on quantum transport in carbon nanotubes

We report first-principles calculations of conductance of carbon nanotubes between metallic electrodes. The electronic states are calculated using a numerical atomic orbital basis set in the framework of the density functional theory, and the conductance is calculated using the Green's function method. We show transmission spectra of carbon nanotubes connected to electrodes and reveal the contact effect of electrodes on the transport properties of nanotubes.

Pathways for oxygen adsorption on single-wall carbon nanotubes

Effects of oxygen adsorption on the structural and transport properties of single wall carbon nanotubes (SWCN's) are investigated in detail using ab initio and generalized tight-binding molecular-dynamics methods. We findthat the oxygen-SWCN interaction depends strongly on the spin configuration which, in turn, specifies oxygen's adsorption pathway. In the case of a single oxygen, the most stable adsorption site is one in which the O atom sits on a C-C bridge, breaking the underlying C-C bond. For the O 2 molecule, the adsorption geometry is found to depend sensitively on the curvature of the nanotube. Our calculations also show that the transport properties of nanotubes are significantly affected by the presence of oxygen.