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Magnetic behaviour of Eu_2CuSi_3: Large negative magnetoresistance above Curie temperature

Subham Majumdar·R. Mallik·E. V. Sampathkumaran·Kirsten Rupprecht·G. Wortmann
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Abstract

We report here the results of magnetic susceptibility, electrical-resistivity, magnetoresistance (MR), heat-capacity and ^{151}Eu Mossbauer effect measurements on the compound, Eu_2CuSi_3, crystallizing in an AlB_2-derived hexagonal structure. The results establish that Eu ions are divalent, undergoing long-range ferromagnetic-ordering below (T_C=) 37 K. An interesting observation is that the sign of MR is negative even at temperatures close to 3T_C, with increasing magnitude with decreasing temperature exhibiting a peak at T_C. This observation, being made for a Cu containing magnetic rare-earth compound for the first time, is of relevance to the field of collosal magnetoresistance.

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Subham Majumdar, R. Mallik, E. V. Sampathkumaran, Kirsten Rupprecht, G. Wortmann. 1999-05-28. Magnetic behaviour of Eu_2CuSi_3: Large negative magnetoresistance above Curie temperature. https://doi.org/10.1103/physrevb.60.6770

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