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The magnetoresistance in GdNi: Magnetic-polaronic-like effect near Curie temperature and low temperature sign reversal

R. Mallik·E. V. Sampathkumaran·P. L. Paulose·V. Nagarajan
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Abstract

The results of magnetoresistance ($Δρ/ρ$)measurements in GdNi, in the temperature range 4.2 to 300 K are reported. The sign of $Δρ/ρ$ above the Curie temperature (Tc= 70 K) is negative and its magnitude in a magnetic field of 80kOe grows with decreasing temperature below 150 K with a peak value of about -20% at Tc. These features, qualitatively resembling those in giant magnetoresistance systems (manganates), are attributed to the formation of some kind of magnetic polarons induced by Gd. The magnetoresistance changes sign below 12 K which is attributed to subtle band structure effects.

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R. Mallik, E. V. Sampathkumaran, P. L. Paulose, V. Nagarajan. 1998-12-04. The magnetoresistance in GdNi: Magnetic-polaronic-like effect near Curie temperature and low temperature sign reversal. https://arxiv.org/abs/cond-mat/9812069

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