Quantum interference effects in electronic transport through nanotube contacts

Quantum interference has dramatic effects on electronic transport through nanotube contacts. In optimal configuration the intertube conductance can approach that of a perfect nanotube (4e(2)/h). The maximum conductance increases rapidly with the contact length up to 10 nm, beyond which it exhibits long-wavelength oscillations. This is attributed to the resonant interference phenomena in the contact region. For two concentric nanotubes symmetry breaking can reduce the maximum intertube conductance from 4e(2)/h to 2e(2)/h. The phenomena discussed here can serve as a foundation for building nanotube electronic circuits and high-speed nanoscale electromechanical devices.