
Lobos, A. M., A. A. Aligia, and J. G. Sereni. "Specific heat of magnetic Ce alloys within a twocomponent 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 X0 (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 nonFermi 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.



Pedrazzini, P., M. G. Berisso, N. CarocaCanales, M. Deppe, C. Geibel, and J. G. Sereni. "Low temperature magnetic phase diagram of the cubic nonFermi liquid system Celn(3x)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 (CP), down to 0.5 K of the cubic CeIn3xSnx alloy. The ground state of this system evolves from antiferromagnetic (AF) in CeIn3 (TN = 10.2 K) to intermediatevalent in CeSn3, and represents the first example of a Celattice cubic nonFermi liquid (NFL) system where TN(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 Tn (with n < 1.5) and CP(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 CP/T shows only a weak temperature dependence.

