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arXiv · 1107.1975

Magnetic and magnetoresistive properties of cubic Laves phase HoAl$_2$ single crystal

M. Patra·S. Majumdar·S. Giri·Y. Xiao·T. Chatterji
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Abstract

We report the magnetization ($M$) and magnetoresistance (MR) results of HoAl$_2$ single crystals oriented along $<100>$ and $<110>$ directions. Although HoAl$_2$ has cubic Laves phase structure, a large anisotropy is observed in $M$ and MR results below Curie temperature ($T_C$) at 31.5 K. A satisfactory correlation between magnetic entropy change ($\Delta S_M$) and MR could be established along $<110>$ direction and in $<100>$ direction except for the temperature ($T$) region, around which spin reorientation takes place. Large inverse magnetocaloric effect is observed at low-$T$ which is associated with the spin reorientation process in $<100>$ direction. A theoretical model based on Landau theory of phase transition can describe $T$-variation of -$\Delta S_M$ for $T > T_C$.

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M. Patra, S. Majumdar, S. Giri, Y. Xiao, T. Chatterji. 2011-07-11. Magnetic and magnetoresistive properties of cubic Laves phase HoAl$_2$ single crystal. https://arxiv.org/abs/1107.1975

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