Sereni, J. G., T. Radu, and A. Pikul. "Analysis of the very low temperature phase diagrams of two Ce compounds." Journal of Optoelectronics and Advanced Materials 10, no. 7 (2008): 1645–1650.
Abstract: A rich variety of behaviours have been found studying the physical properties of Ce-lattice systems tuned around their critical regions, particularly in the few phase boundaries traced along more than a decade of temperature. The phase diagram of two Ce-systems: the antiferromagnetic CeIn3-xSnx and ferromagnetic CePd1-xRhx are analyzed covering the 10K > T > 0.02K range of temperature. Their respective magnetic phase diagrams are described as an interplay between different components determined after analyzing their thermodynamic properties. In the former compound, signs for the formation of a new phase are observed at very low temperature, whereas in the latter a field induced contribution is detected behind the critical point.
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Hartmann, S., M. Deppe, N. Oeschler, N. Caroca-Canales, J. G. Sereni, and C. Geibel. "Ferromagnetism in CePd1-xRhx single crystals." Journal of Optoelectronics and Advanced Materials 10, no. 7 (2008): 1607–1611.
Abstract: The orthorhombic CePd1-xRhx alloy exhibits a continuous evolution from a ferromagnetic ground state at x = 0 to
intermediate-valence behavior for x = 1. Here, we report on specific heat CP(T), resistivity Ï(T) and magnetization M(T)
measurements on single crystals in a Rh concentration range 0.2 < x < 0.65 exploring the ferromagnetic side of the
magnetic phase diagram. The transport and thermodynamic properties of the ferromagnetic phase have been investigated
in the temperature range from 300 K down to 0.35 K and analyzed in terms of a gap in the magnon spectrum and an
underlying Kondo contribution. Crystal electric field parameters are deduced from specific heat measurements well above
Tc- The competition between Kondo effect and ferromagnetism has been studied in dependence of the Rh concentration in
the system. Particularly, the enhanced Sommerfeld coefficient γ(x) indicates strong Kondo interactions when the Curie
temperature is reduced.
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