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Updated: Jun 2, 2026

Simultaneous Synthesis of Single-walled Carbon Nanotubes and Graphene in a Magnetically-enhanced Arc Plasma
Published on: February 2, 2012
Helical modes in carbon nanotubes generated by strong electric fields
Jelena Klinovaja1, Manuel J Schmidt, Bernd Braunecker
1Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland.
Abstract:
Helical modes, conducting opposite spins in opposite directions, are shown to exist in metallic armchair nanotubes in an all-electric setup. This is a consequence of the interplay between spin-orbit interaction and strong electric fields. The helical regime can also be obtained in chiral metallic nanotubes by applying an additional magnetic field. In particular, it is possible to obtain helical modes at one of the two Dirac points only, while the other one remains gapped. Starting from a tight-binding model we derive the effective low-energy Hamiltonian and the resulting spectrum.
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