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arXiv · 1207.0519

Evolution of the magnetism of Tb(Co_{x}Ni_{1-x})_{2}B_{2}C

M. ElMassalami·H. Takeya·A. M. Gomes·T. Paiva·R. R. dos Santos
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Abstract

The magnetic properties of polycrystalline Tb(Co_{x}Ni_{1-x})_{2}B_{2}C (x=0.2,0.4,0.6,0.8) samples were probed by magnetization, specific heat, ac susceptibility, and resistivity techniques. For x{\neq}0.4, the obtained curves are consistent with the features expected for the corresponding magnetic modes, namely k_{1}=(0.55,0,0) at x=0; k_{2}=([nicefrac]\nicefrac{1}{2} ,0,[nicefrac] \nicefrac{1}{2}) at x= 0.2; k_{3}=(0,0,[nicefrac]\nicefrac{1}{3}) at x= 0.6, and k_{4}=(0,0,0) at x= 0.8 and 1. For x=0.4, even though the neutron diffraction indicates a k_{2} mode, but with a reduced magnetic moment, the magnetization, the ac susceptibility, and resistivity indicate two magnetic events; furthermore, deviation from Curie-Weiss behavior is observed below 150 K for this sample. These features, together with the evolution of both magnetic moment and critical temperature, are attributed to an interplay between competing magnetic couplings; for the particular x=0.4 case, additional factors such as crystalline electric field effects may be in operation.

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M. ElMassalami, H. Takeya, A. M. Gomes, T. Paiva, R. R. dos Santos. 2012-07-02. Evolution of the magnetism of Tb(Co_{x}Ni_{1-x})_{2}B_{2}C. https://doi.org/10.1016/j.jmmm.2014.07.026

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