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arXiv · 1501.02996

The Electronic and Magnetic Properties of Magnetoresistant Nd1-xSrxMnAsO Oxyarsenides

E. J. Wildman·N. Emery·A. C. Mclaughlin
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Abstract

The oxypnictides Nd1-xSrxMnAsO have been successfully synthesised with x up to 0.1. A synchrotron X-ray diffraction study demonstrates that there is no change in crystal symmetry upon doping with Sr. An expansion of the inter-layer distance between Nd-O-Nd and As-Mn-As blocks is observed with increasing x. Results from variable temperature neutron diffraction and resistivity measurements show that the local moment antiferromagnetic order of the Mn spins is preserved as the [MnAs]- layers are hole doped and the materials are driven metallic for x > 0.05. A sizeable positive magnetoresistance is observed at low temperature which demonstrates that multiple MR mechanisms are possible in LnMnAsO oxypnictides.

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E. J. Wildman, N. Emery, A. C. Mclaughlin. 2015-01-13. The Electronic and Magnetic Properties of Magnetoresistant Nd1-xSrxMnAsO Oxyarsenides. https://doi.org/10.1103/physrevb.90.224413

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