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arXiv · 0802.1018

High-field and low field magnetoresistance of CoFe nanoparticles elaborated by organometallic chemistry

Reasmey P. Tan·Julian Carrey·Marc Respaud·Celine Desvaux·Philippe Renaud·Bruno Chaudret
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Abstract

We report on magnetotransport measurements on CoFe nanoparticles surrounded by an insulating organic layer. Samples were obtained by evaporating a solution of nanoparticles on a patterned substrate. Typical behaviour of Coulomb blockade in array of nanoparticles is observed. High and low field magnetoresistance have been evidenced. Below 10 K, a large high-field magnetoresistance is measured, reaching up to 500 %. Its amplitude decreases strongly with increasing voltage. At 1.6 K, this high-field magnetoresistance vanishes and an inverse low field tunnelling magnetoresistance is observed.

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Reasmey P. Tan, Julian Carrey, Marc Respaud, Celine Desvaux, Philippe Renaud, Bruno Chaudret. 2008-02-07. High-field and low field magnetoresistance of CoFe nanoparticles elaborated by organometallic chemistry. https://doi.org/10.1063/1.2838621

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