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Enhanced electrical resistivity before Néel order in the metals, RCuAs$_2$ (R= Sm, Gd, Tb and Dy

E. V. Sampathkumaran·Kausik Sengupta·S. Rayaprol·Kartik K. Iyer·Th. Doert·J. P. F. Jemetio
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Abstract

We report an unusual temperature (T) dependent electrical resistivity($ρ$) behavior in a class of ternary intermetallic compounds of the type RCuAs$_2$ (R= Rare-earths). For some rare-earths (Sm, Gd, Tb and Dy) with negligible 4f-hybridization, there is a pronounced minimum in $ρ$(T) far above respective Néel temperatures (T$_N$). However, for the rare-earths which are more prone to exhibit such a $ρ$(T) minimum due to 4f-covalent mixing and the Kondo effect, this minimum is depressed. These findings, difficult to explain within the hither-to-known concepts, present an interesting scenario in magnetism.

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E. V. Sampathkumaran, Kausik Sengupta, S. Rayaprol, Kartik K. Iyer, Th. Doert, J. P. F. Jemetio. 2003-06-11. Enhanced electrical resistivity before Néel order in the metals, RCuAs$_2$ (R= Sm, Gd, Tb and Dy. https://doi.org/10.1103/physrevlett.91.036603

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