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arXiv · 1207.0958

Colossal Magnetoresistance in the Mn2+ Oxypnictides NdMnAsO1-xFx

E. J. Wildman·J. M. S. Skakle·N. Emery·A. C. Mclaughlin
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Abstract

Colossal magnetoresistance (CMR) is a rare phenomenon in which the electronic resistivity of a material can be decreased by orders of magnitude upon application of a magnetic field. Such an effect could be the basis of the next generation of magnetic memory devices. Here we report CMR in the antiferromagnetic oxypnictide NdMnAsO1-xFx as a result of competition between an antiferromagnetic insulating phase with strong electron correlations and a paramagnetic semiconductor upon application of a magnetic field. The discovery of CMR in antiferromagnetic Mn2+ oxypnictide materials could open up an array of materials for further investigation and optimisation for technological applications.

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E. J. Wildman, J. M. S. Skakle, N. Emery, A. C. Mclaughlin. 2012-07-04. Colossal Magnetoresistance in the Mn2+ Oxypnictides NdMnAsO1-xFx. https://doi.org/10.1021/ja302328t

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