1203.3273 (Ryo Tamura)

Relation between dispersion lines and conductance of telescoped armchair
double-wall nanotubes analyzed using perturbation formulas and
first-principles calculations    [PDF]

Ryo Tamura

The approximate analytical formulas for a tight binding Hamiltonian [R. Tamura, Phys. Rev. B {\bf 82} 035415 (2010)] are generalized for a Hamiltonian defined by first-principles calculations. Considering the interlayer Hamiltonian as a perturbation, we obtain approximate formulas for the conductance of a telescoped double-wall nanotube and for the dispersion lines of an un-telescoped double-wall nanotube. Herein, partially extracting the inner tube from the outer tube is called 'telescoping'. The effectiveness of the approximate formulas is confirmed by their agreement with exact calculations. Interlayer interactions between the anti-symmetric states are strongly suppressed by the wide spatial range of the interlayer Hamiltonian. Therefore, the symmetric states are dominant in the conductance as a function of the overlap length, which showed a rapid oscillation superposed on a slow oscillation. Relationship between the slow oscillation and the dispersion lines is described on the analogy of the Thouless number.

View original: http://arxiv.org/abs/1203.3273