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Magnetoresistance of metallic perovskite oxide LaNiO$_{3-δ}$

N. Gayathri·A. K. Raychaudhuri·X. Q. Xu·J. L. Peng·R. L. Greene
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Abstract

We report a study of the magnetoresistance (MR) of the metallic perovskite oxide LaNiO$_{3-δ}$ as a function of the oxygen stoichiometry $δ$ ($δ\leq$ 0.14), magnetic field (H $\leq 6T$) and temperature (1.5K $\leq $ T $\leq $ 25K). We find a strong dependence of the nature of MR on the oxygen stoichiometry. The MR at low temperatures change from positive to negative as the sample becomes more oxygen deficient (i.e, $δ$ increases). Some of the samples which are more resistive, show a resistivity minima at $T_{min}$ $\approx$ 20K. We find that in these samples the MR is positive at T > $T_{min}$ and negative for T < $T_{min}$. We conclude that in the absence of strong magnetic interaction, the negative MR in these oxides can arise from weak localisation effects.

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N. Gayathri, A. K. Raychaudhuri, X. Q. Xu, J. L. Peng, R. L. Greene. 1998-07-24. Magnetoresistance of metallic perovskite oxide LaNiO$_{3-δ}$. https://doi.org/10.1088/0953-8984%2F11%2F14%2F006

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