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Observation of a temperature dependent electrical resistance minimum above the magnetic ordering temperature in Gd$_2$PdSi$_3$

R. Mallik·E. V. Sampathkumaran·M. Strecker·G. Wortmann
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Abstract

Results on electrical resistivity, magnetoresistance, magnetic Results on electrical resistivity, magnetoresistance, magnetic susceptibility, heat capacity and Gd Mossbauer measurements on a Gd-based intermetallic compound, Gd$_{2}$PdSi$_{3}$ are reported. A finding of interest is that the resistivity unexpectedly shows a well-defined minimum at about 45 K, well above the long range magnetic ordering temperature (21 K), a feature which gets suppressed by the application of a magnetic field. This observation in a Gd alloy presents an interesting scenario. On the basis of our results, we propose electron localization induced by s-f (or d-f) exchange interaction prior to long range magnetic order as a mechanism for the electrical resistance minimum.

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R. Mallik, E. V. Sampathkumaran, M. Strecker, G. Wortmann. 1998-11-27. Observation of a temperature dependent electrical resistance minimum above the magnetic ordering temperature in Gd$_2$PdSi$_3$. https://doi.org/10.1209/epl%2Fi1998-00149-4

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