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arXiv · 0808.2826

Crystal Growth and Anisotropic Magnetic Properties of RAg$_2$Ge$_2$ (R = Pr, Nd and Sm) Single Crystals

Devang A. Joshi·R. Nagalakshmi·R. Kulkarni·S. K. Dhar·A. Thamizhavel
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Abstract

We report the single crystal growth and anisotropic magnetic properties of the tetragonal RAg$_2$Ge$_2$ (R = Pr, Nd and Sm) compounds which crystallize in the ThCr$_2$Si$_2$ type crystal structure with the space group \textit{I4/mmm}. The single crystals of RAg$_2$Ge$_2$ (R = Pr, Nd and Sm) were grown by self-flux method using Ag:Ge binary alloy as flux. From the magnetic studies on single crystalline samples we have found that PrAg$_2$Ge$_2$ and NdAg$_2$Ge$_2$ order antiferromagnetically at 12 K and 2 K respectively, thus corroborating the earlier polycrystalline results. SmAg$_2$Ge$_2$ also orders antiferromagnetically at 9.2 K. The magnetic susceptibility and magnetization show a large anisotropy and the easy axis of magnetization for PrAg$_2$Ge$_2$ and NdAg$_2$Ge$_2$ is along the [100] direction where as it changes to [001] direction for SmAg$_2$Ge$_2$. Two metamagnetic transitions were observed in NdAg$_2$Ge$_2$ at $H_{\rm m1}$ = 1.25 T and $H_{\rm m2}$ =3.56 T for the field parallel to [100] direction where as the magnetization along [001] direction was linear indicating the hard axis of magnetization.

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Devang A. Joshi, R. Nagalakshmi, R. Kulkarni, S. K. Dhar, A. Thamizhavel. 2008-08-20. Crystal Growth and Anisotropic Magnetic Properties of RAg$_2$Ge$_2$ (R = Pr, Nd and Sm) Single Crystals. https://doi.org/10.1016/j.physb.2009.07.016

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