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Large magnetoresistance in low temperature metallic region of manganite compounds (La0.7-2xEux)(Ca0.3Srx)MnO3 (0.05<x<0.15)

D. S. Rana·C. M. Thaker·K. R. Mavani·D. G. Kuberkar·S. K. Malik
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Abstract

Magnetoresistance (MR) and magnetization (d.c and a.c) measurements have been carried out on the manganites, (La0.7-2xEux)(Ca0.3Srx)MnO3 (0.05<x<0.15), in the temperature range of 5K-320K. At 5K, an unusually large MR of almost 98% is observed in the x=0.15 sample, nearly up to fields of 4-5 Tesla. This large high-field MR occurs in the metallic region, far below the insulator-metal transition temperature, and does not vary linearly with applied field. The unusual magnetoresistance is explained the light of various possibilities of phase segregation and cluster spin-glass behavior. Keywords: Manganites, High field MR, Phase segregation.

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D. S. Rana, C. M. Thaker, K. R. Mavani, D. G. Kuberkar, S. K. Malik. 2004-12-16. Large magnetoresistance in low temperature metallic region of manganite compounds (La0.7-2xEux)(Ca0.3Srx)MnO3 (0.05<x<0.15). https://doi.org/10.1016/j.ssc.2004.12.015

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