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arXiv · 1302.4226

Observation of large positive magnetoresistance and its sign reversal in GdRhGe

Sachin Gupta·K. G. Suresh·A. K. Nigam
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Abstract

Magnetic properties, heat capacity and magnetoresistance (MR) of polycrystalline GdRhGe are investigated. It shows two antiferromagnetic transitions, one at T1=31.8 K and the other at T2=24 K, and field induced metamagnetic transition over a wide temperature range. The ac susceptibility data reveal that the transition at 24 K is not simple antiferromagnetic. Dominant contributions to the heat capacity and the resistivity have been identified. MR is found to show sign reversal just below T1 and attains a large positive value of 48% at 2 K for 50 kOe. Like MR, the isothermal magnetic entropy change also undergoes a sign reversal as the temperature is varied, indicating a change of the magnetic structure and the moment amplitude in determining these properties.

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Sachin Gupta, K. G. Suresh, A. K. Nigam. 2013-02-18. Observation of large positive magnetoresistance and its sign reversal in GdRhGe. https://doi.org/10.1016/j.jallcom.2013.10.123

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