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Investigation of electrical transport in hydrogenated multiwalled carbon nanotubes

Department of Physics, Northeastern University, Boston, MA 02115, USA; Code 6876, US Naval Research Laboratory, Washington, DC 20375, USA; Department of Mechanical and Industrial Engineering, Northeastern University, Boston, MA 02115, USA
Physica B Condensed Matter (Impact Factor: 1.28). 01/2011; DOI: 10.1016/j.physb.2010.12.009

ABSTRACT Highly disordered multiwalled carbon nanotubes of large outer diameter (∼60 nm) fabricated by means of chemical vapor deposition process inside porous alumina templates exhibit ferromagnetism when annealed in a H2/Ar atmosphere. In the presence of an applied magnetic field, there is a transition from positive to negative magnetoresistance. The transition may be explained in terms of the Bright model for ordered and disordered carbon structures. Additionally, temperature dependent electrical transport experiments exhibit a zero-bias anomaly at low temperature.

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