Defective transport properties of three-terminal carbon nanotube junctions

Abstract

We investigate the transport properties of three terminal carbon based nanojunctions within the scattering matrix approach. The stability of such junctions is subordinated to the presence of nonhexagonal arrangements in the molecular network. Such "defective" arrangements do influence the resulting quantum transport observables, as a consequence of the possibility of acting as pinning centers of the correspondent wavefunction. By investigating a fairly wide class of junctions we have found regular mutual dependencies between such localized states at the carbon network and a strikingly behavior of the conductance. In particular, we have shown that Fano resonances emerge as a natural result of the interference between defective states and the extended continuum background. As a consequence, the currents through the junctions hitting these resonant states might experience variations on a relevant scale with current modulations of up to 75%.

Coherent charge transport through molecular wires: Influence of strong Coulomb repulsion

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Scaling of the conductance in gold nanotubes

“…To deal with such semi-infinite leads, we adopt a recursive renormalization procedure already described in Ref. 23. Considering the leads as bulk gold will yield an increased imaginary part of the lead self-energies, which will slightly decrease the conductance values.…”

Thermal conductivity of an ultrathin carbon nanotube with an X-shaped junction

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“…Experimental and theoretical studies [3][4][5][6][7] have shown that both the symmetry of the Y junction and the chirality of the trunk and branches play a role in the rectification behavior of these structures, with the symmetry being a more significant factor. It is therefore important to know how the topological defects influence the thermal conduction properties of CNTs.…”