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arXiv · 1503.00579

Magnetic order and superconductivity observed in bundles of Double-Wall Carbon Nanotubes

J. Barzola-Quiquia·P. Esquinazi·M. Lindel·D. Spemann·M. Muallem·G. D. Nessim
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Abstract

The magnetotransport properties were studied in hundreds of micrometer length double-wall carbon nanotubes (DWCNT) bundles. Above 15 K the resistance shows an ohmic behavior and its temperature dependence is well described using the variable-range hopping for one-dimensional system. The magnetoresistance is negative and can be explained using an empirical model based on spin-scattering processes indicating the existence of magnetic order up to room temperature. At temperatures between 2 K and 15 K the resistance is non-ohmic and the current-voltage characteristics reveal the appearance of a potential, which can be well described by a fluctuation-induced tunneling conduction model. In this low temperature range and at low enough input current, a positive magnetoresistance appears - in addition to the negative one - with an extraordinary hysteresis in field and vanishes at $T \sim 15 $K, suggesting the existence of a superconducting state. Magnetization results partially support the existence of both phenomena in the DWCNT bundles.

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J. Barzola-Quiquia, P. Esquinazi, M. Lindel, D. Spemann, M. Muallem, G. D. Nessim. 2015-03-02. Magnetic order and superconductivity observed in bundles of Double-Wall Carbon Nanotubes. https://arxiv.org/abs/1503.00579

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