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arXiv · 1708.01047

Different metamagnetism between paramagnetic Ce and Yb isomorphs

Atsushi Miyake·Yoshiaki Sato·Masashi Tokunaga·Jumaeda Jatmika·Takao Ebihara
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Abstract

To solve the puzzle of metamagnetic phenomena in heavy fermion systems, we have compared paramagnetic isostructural Ce and Yb systems, CeNi$_2$Ge$_2$ and YbNi$_2$Ge$_2$, both of which are located near a magnetic instability. The most intriguing result is discovery of a metamagnetic-like transition in both systems from magnetization measurements in a pulsed magnetic fields. This is the first observation of the metamagnetism for isomorphic Ce and Yb paramagnetic systems. Similar to other metamagnets, the metamagnetic transition fields for both compounds are well scaled by the temperature $T_χ^{\rm max}$, at which the magnetic susceptibility shows a maximum. In addition, for CeNi$_2$Ge$_2$ a peak of nonlinear susceptibility $χ_3$ appears at approximately $T_χ^{\rm max}/2$, as for other heavy-fermion metamagnets. In contrast, YbNi$_2$Ge$_2$ shows only a sign change for $χ_3$ at $T_χ^{\rm max}$, as observed in itinerant metamagnets located near the ferromagnetic critical point. The metamagnetism of CeNi$_2$Ge$_2$ corresponds to a typical Kondo lattice system, whereas that of YbNi$_2$Ge$_2$ is similar to the nearly ferromagnetic itinerant systems. Other possibilities for the metamagnetic behavior of YbNi$_2$Ge$_2$ are also discussed.

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Atsushi Miyake, Yoshiaki Sato, Masashi Tokunaga, Jumaeda Jatmika, Takao Ebihara. 2017-08-03. Different metamagnetism between paramagnetic Ce and Yb isomorphs. https://doi.org/10.1103/physrevb.96.085127

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