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Magnetoresistance in ordered and disordered double perovskite oxide, Sr$_2$FeMoO$_6$

D. D. Sarma·E. V. Sampathkumaran·Sugata Ray·R. Nagarajan·Subham Majumdar·Ashwani Kumar·G. Nalini·T. N. GuruRow
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Abstract

We have prepared crystallographically ordered and disorder specimens of the double perovskite, Sr$_2$FeMoO$_6$ and investigated their magnetoresistance behaviour. The extent of ordering between the Fe and Mo sites in the two samples is determined by Rietveld analysis of powder x-ray diffraction patterns and reconfirmed by Mössbauer studies. While the ordered sample exhibits the sharp low-field response, followed by moderate changes in the magnetoresistance at higher fields, the disordered sample is characterised by the absence of the spectacular low-field response. We argue that the low field response depends crucially on the half-metallic ferromagnetism, while the high-field response follows from the overall magnetic nature of the sample, even in absence of the half-metallic state.

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D. D. Sarma, E. V. Sampathkumaran, Sugata Ray, R. Nagarajan, Subham Majumdar, Ashwani Kumar, G. Nalini, T. N. GuruRow. 2000-03-14. Magnetoresistance in ordered and disordered double perovskite oxide, Sr$_2$FeMoO$_6$. https://doi.org/10.1016/s0038-1098(00)00079-x

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