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arXiv · 1106.3332

Carbon nanotubes in electric and magnetic fields

Jelena Klinovaja·Manuel J. Schmidt·Bernd Braunecker·Daniel Loss
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Abstract

We derive an effective low-energy theory for metallic (armchair and non-armchair) single-wall nanotubes in the presence of an electric field perpendicular to the nanotube axis, and in the presence of magnetic fields, taking into account spin-orbit interactions and screening effects on the basis of a microscopic tight binding model. The interplay between electric field and spin-orbit interaction allows us to tune armchair nanotubes into a helical conductor in both Dirac valleys. Metallic non-armchair nanotubes are gapped by the surface curvature, yet helical conduction modes can be restored in one of the valleys by a magnetic field along the nanotube axis. Furthermore, we discuss electric dipole spin resonance in carbon nanotubes, and find that the Rabi frequency shows a pronounced dependence on the momentum along the nanotube.

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Jelena Klinovaja, Manuel J. Schmidt, Bernd Braunecker, Daniel Loss. 2011-06-16. Carbon nanotubes in electric and magnetic fields. https://doi.org/10.1103/physrevb.84.085452

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