Lobos, A. M., A. A. Aligia, and J. G. Sereni. "Specific heat of magnetic Ce alloys within a two-component model." European Physical Journal B 41, no. 3 (2004): 289–294.
Abstract: We propose a description of the electronic properties of Ce alloys as an inhomogeneous mixture of two components: one containing magnetic Ce ions with an RKKY interaction J(H) between them, and the other described as a collection of Kondo impurities with exchange interaction J(K). Both J(H) and J(K) are assumed to depend on a composition parameter X, with a Gaussian distribution around a value X-0 (near to the expectation value of X), related to the experimental composition parameter x of the alloy. When the concentration of the Kondo impurities is large, the specific heat C displays non-Fermi liquid behavior over a wide temperature range. The main qualitative features of C/T as a function of temperature T observed in several Ce alloys are reproduced using simple J(H)(X) and J(K)(X) dependences.
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Pedrazzini, P., M. G. Berisso, N. Caroca-Canales, M. Deppe, C. Geibel, and J. G. Sereni. "Low temperature magnetic phase diagram of the cubic non-Fermi liquid system Celn(3-x)Sn(x)." The European Physical Journal B – Condensed Matter 38, no. 3 (2004): 445–450.
Abstract: In this paper we report a comprehensive study of the magnetic susceptibility (x), resistivity (p), and specific heat (C-P), down to 0.5 K of the cubic CeIn3-xSnx alloy. The ground state of this system evolves from antiferromagnetic (AF) in CeIn3 (T-N = 10.2 K) to intermediate-valent in CeSn3, and represents the first example of a Ce-lattice cubic non-Fermi liquid (NFL) system where T-N(x) can be traced down to T = 0 over more than a decade of temperature. Our results indicate that the disappearance of the AF state occurs near x(c) approximate to 0.7, although already at x approximate to 0.4 significant modifications of the magnetic ground state are observed. Between these concentrations, clear NFL signatures are observed, such as rho(T) approximate to rho(0) + A T-n (with n < 1.5) and C-P(T) proportional to -T ln(T) dependencies. Within the ordered phase a first order phase transition occurs for 0.25 < x < 0.5. With larger Sn doping, different weak rho(T) dependencies are observed at low temperatures between x = 1 and x = 3 while C-P/T shows only a weak temperature dependence.
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