60 research outputs found
Spin-orbit interaction in the graphitic nanocone
The Hamiltonian for nanocones with curvature induced spin orbit coupling have
been derived. The effect of curvature induced spin orbit coupling on the
electronic properties of graphitic nanocones is considered. Energy spectra for
different numbers of the pentagonal defects in the tip of the nanocones are
calculated. It was shown that the spin orbit interaction considerably affects
the local density of states of the graphitic nanocone. This influence depends
on the number of defects present at the tip of the nanocone. This property
could be applied in atomic force microscopy for the construction of the probing
tip.Comment: 8 pages, 4 figures, 1 tabl
Spin-orbit effects in armchair carbon nanotubes: analytical results
Energy spectra and transport properties of armchair nanotubes with curvature
induced spin-orbit interaction are investigated thoroughly. The spin-orbit
interaction consists of two terms: the first one preserves the spin symmetry in
rotating frame, while the second one breaks it. It is found that the both terms
are equally important: i)at scattering on the potential step which mimics a
long-range potential in the nanotubes; ii)at transport via nanotube quantum
dots. It is shown that an armchair nanotube with the first spin-orbit term
works as an ideal spin-filter, while the second term produces a parasitic
inductance.Comment: 11 pages, 10 figure
Electronic properties of double-layer carbon nanotubes
The electronic spectra for double-wall zigzag and armchair nanotubes are
found. The influence of nanotube curvatures on the electronic spectra is also
calculated. Our finding that the outer shell is hole doped by the inner shell
is in the difference between Fermi levels of individual shells which originate
from the different hybridization of pi-orbital. The shift and rotation of the
inner nanotube with respect to the outer nanotube are investigated. We found
stable semimetal characteristics of the armchair DWNTs in regard of the shift
and rotation of the inner nanotube. We predict the shift of k_F towards the
bigger wave vectors with decreasing of the radius of the armchair nanotube.Comment: 26 pages, 10 figures. European Physical Journal B, in press,
Condensed Matter - Mesoscopic and Nanoscale System
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