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arXiv · 1205.3092

Partially unzipped carbon nanotubes as magnetic field sensors

S. Costamagna·A. Schulz·L. Covaci·F. Peeters
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Abstract

The conductance, $G(E)$, through graphene nanoribbons (GNR) connected to a partially unzipped carbon nanotube (CNT) is studied in the presence of an external magnetic field applied parallel to the long axis of the tube by means of non-equilibrium Green's function technique. We consider (z)igzag and (a)rmchair CNTs that are partially unzipped to form aGNR/zCNT/aGNR or zGNR/aCNT/zGNR junctions. We find that the inclusion of a longitudinal magnetic field affects the electronic states only in the CNT region, leading to the suppression of the conductance at low energies. Unlike previous studies, for the zGNR/aCNT/zGNR junction in zero field, we find a sharp dip in the conductance as the energy approaches the Dirac point and we attribute this non-trivial behavior to the peculiar band dispersion of the constituent subsystems. We demonstrate that both types of junctions can be used as magnetic field sensors.

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S. Costamagna, A. Schulz, L. Covaci, F. Peeters. 2012-05-14. Partially unzipped carbon nanotubes as magnetic field sensors. https://doi.org/10.1063/1.4726039

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