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Gastaldo, F., S. Gabáni, A. Džubinská, M. Reiffers, G. PristáÅ¡, I. ÄŒurlík, P. Skyba, M. Clovecko, F. Vavrek, J. G. Sereni et al. "YbPd2In: A promising candidate for strong entropy accumulation at very low temperature." Physical Review B 100, no. 17 (2019): 174422.
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Gomez Berisso, M., J. G. Sereni, A. Braghta, G. Schmerber, B. Chevalier, and J. P. Kappler. "Field suppression of the modulated phase of Ce2Pd2Sn." Physica B 404, no. 19 (2009): 2930–2933.
Abstract: Low temperature magnetic (M) and thermal (CP) properties of the intermetallic compound Ce2Pd2Sn have been investigated at zero and different magnetic fields. Two transitions were recognized at and , with latter nearly coinciding with the extrapolated Curie-Weiss temperature . The Curie factor evaluated from T>=TM, is [approximate]2μB. The positive value of θP, the triangular coordination of the magnetic (Ce) atoms and the weak effect of applied magnetic field, reveal that TM cannot be considered as a canonic antiferromagnetic transition like claimed in the literature. M(T) measurements under moderate magnetic fields () show TC(B) increasing while TM(B) is practically not affected. Both transition merge in a critical point at for , where the intermediate phase is suppressed. At , the cusp of a first order transition is observed in CP(T). According to the proposed ferromagnetic ground state, it is followed by a CP(T)[is proportional to]T3/2exp(-Eg/T) dependence, with a gap of anisotropy .
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Gomez-Berisso, M., P. Pedrazzini, J. G. Sereni, O. Trovarelli, C. Geibel, and F. Steglich. "Low-temperature properties of the Ce(Pd1-rRhr)(2)Si-2 system." PHYSICA B 258-261 (1999): 68–69.
Abstract: The ground state of the Ce(Pd1-rRhr)(2)Si-2 system is studied by means of magnetic susceptibility and low-temperature specific heat measurements (Cp) throughout the concentration range. The antiferromagnetic order of both stoichiometric extremes (T-N = 10.3 and 36 K for r = 0 and 1, respectively) drops abruptly below 0.4 K with mon than 30% of Pd substitution by Rh and 20% of Rh substitution by Pd on the respective sides. No magnetic order is observed between those concentrations, where the low-temperature behaviour is characterized by a C-P(T --> 0)/T divergency that continuously decreases (like the asociated entropy gain) as the Ph concentration increases. (C) 1999 Elsevier Science B.V. All rights reserved.
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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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Huber, J. G., J. B. Bulman, and J. G. Sereni. "Superconductivity under pressure and low temperature specific heat of ThPr alloys." Solid State Communications 43, no. 12 (1982): 925–931.
Abstract: Measurements of superconducting transition temperature under pressure and low temperature specific heat are presented for ThPr alloys. At 18.2 kbar the normal- to superconducting-state phase boundary extends beyond 50 at.% Pr. This system is discussed in terms of a non-magnetic singlet ground state for the Pr3+ ions due to crystal field splitting. A splitting scheme which varies with Pr concentration is proposed.
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Kappler, J. P., G. Nieva, J. G. Sereni, and J. Souletie. "Static Scaling in the CePd3Bx Kondo system." Journal de Physique Colloques 49, no. C-8 (1988): 725–726.
Abstract: The static scaling hypothesis for continuous transitions, extended to cases where Tc < 0, has appropriate features to describe heavy fermions. We present here the application of this model to the specific-heat and susceptibility anomalies for the concentrated Kondo system CePd3Bx (x = 0.4 and 1).
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Kappler, J. P., E. Beaurepaire, G. Krill, C. Godart, G. Nieva, and J. G. Sereni. "Magnetic to non-magnetic transition of Ce induced by volume in Ce(Pd, Ni) and electron concentration in Ce(Pd, Rh)." Journal de Physique Colloques 49, no. C-8 (1988): 723–724.
Abstract: Unit cell volume, magnetic properties and LIII X-ray absorption edge studies in Ce(Pd, M) with M = Ni or Rh show that the Ce demagnetization is mainly driven by volume reduction in Ce(Pd, Ni) and essentially due to the reduction of the d electron number in Ce(Pd, Rh).
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Kappler, J. P., E. Beaurepaire, G. Krill, J. G. Sereni, C. Godart, and G. L. Olcese. "Anomalous behaviour of X-ray absorption observed on the highly correlated cerium nitride (CeN) compound." Journal de Physique I 1 (1991): 1381–1387.
Abstract: In this study, we present recent X-ray Absorption Spectroscopy (XAS) results obtained on highly pure cerium nitride (CeN) compounds. CeN is the “archetype” of the strongly mixed-valent (MV) cerium compounds, where the ground state properties are governed by strong hybridization effects between the 4f and the conduction electrons. We will show that, in clear contradistinction with earlier results, the L ${\rm III,II}$ absorption edges of cerium in CEN do not exhibit the two contributions usually observed in strong MV systems. Indeed, in all cases only one single white line is observed. This anomalous behaviour is related with similar results obtained recently on in-situ prepared CeN studied by both L ${\rm III}$ absorption and Ce 2p X-ray photoemission (XPS). The possible influence of the presence of p conduction states to explain this anomalous behaviour is addressed.
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Kappler, J. P., M. J. Besnus, P. Haen, and J. G. Sereni. "Ce ground state in CePd1-xNix." Physica B: Condensed Matter 230-232 (1997): 162–164.
Abstract: Alloying ferromagnetic CePd (Tc = 6.5 K) with the intermediate valence compound CeNi compresses the lattice, though the ferromagnetic order is present up to x = 0.94 in CePd1−xNix. We report here the competition of magnetic order and Kondo effect, through specific heat, magnetization and resistivity measurements. Detailed results gathered on the x = 0.95 sample show several features suggesting a non-Fermi liquid behaviour which may be due to the proximity to magnetic order: ϱ = ϱ0 + AT1.1 (3 < T ⩽ 30 K) and C/T ∠− ln T(T ⩾ 0.9 K). At lower temperatures C/T tends to saturate at a value of 0.225 J/K2 mol, about three times the value observed for CeNi.
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Kappler, J. P., M. J. Besnus, A. Herr, A. Meyer, and J. G. Sereni. "Crossover between intermediate valence and magnetic order in CeRh1-xPdx." Physica B: Condensed Matter 171, no. 1-4 (1991): 346–349.
Abstract: Magnetic, resistivity and specific-heat measurements on the system CeRh1-xPd(x) are presented. The results indicate a continuous decrease of the hybridization when substituting Pd for Rh in the intermediate-valence compound CeRh. The transition to a magnetically ordered state occurs near x = 0.4. The experimental data suggest the coexistence of Kondo effect and magnetic order for Pd contents around 40-50 at.%. The present results show evidence for a crossover from an IV state with full degeneracy through Kondo-lattice behaviour to a local-moment magnetic state.
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