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On the origin of magnetoresistance in Sr$_2$FeMoO$_6$

D. D. Sarma·Sugata Ray·K. Tanaka·A. Fujimori
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Abstract

We report detailed magnetization ($M$) and magnetoresistance ($MR$) studies on a series of Sr$_2$FeMoO$_6$ samples with independent control on anti-site defect and grain boundary densities. These results, exhibiting a switching-like behavior of $MR$ with $M$, establish that the $MR$ is controlled by the magnetic polarization of grain boundary regions, rather than of the grains within a resonant tunnelling mechanism.

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D. D. Sarma, Sugata Ray, K. Tanaka, A. Fujimori. 2003-11-02. On the origin of magnetoresistance in Sr$_2$FeMoO$_6$. https://arxiv.org/abs/cond-mat/0311013

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