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We report a detailed study of the polymorphic transitions in ternary stannide CeRuSn on high quality single crystals through a combination of x-ray diffraction experiments conducted at 300, 275, and 120 K, and measurements of the thermal expansion, magnetization, and resistivity, along main crystallographic axes. In addition, the transition was followed as a function of pressure up to 0.8 GPa. The present x-ray diffraction data show that the room temperature polymorph consists of the lattice doubled along the c axis with respect to the CeCoAl-type structure consistent with previous reports. Upon cooling, the compound undergoes two successive transitions, first to a quintuple (~290 K) and than to a triple CeCoAl superstructure at ~225 K. The transitions are accompanied by a tremendous volume change due to a strong shrinking of the lattice along the c axis, which is clearly observed in thermal expansion. We advance arguments that the volume collapse originates from an increasing number of crystallographically inequivalent Ce sites and the change of ratio between the short and long Ce-Ru bonds. The observed properties of the polymorphic transition in CeRuSn are reminiscent of theɣ--ɑ transition in elementary cerium, suggesting that similar physics, i.e., a Kondo influenced transition and strong lattice vibrations, might be the driving forces. [ABSTRACT FROM AUTHOR]

The evolution of magnetism and superconductivity in Ce 2 Rh 1− x Pd x In 8 solid solutions has been studied within the entire concentration range by means of thermodynamic and magnetic measurements at ambient pressure and at temperatures between 0.35 K and room temperature. For this purpose, single crystals with Pd concentrations x =0, 0.10, 0.15, 0.30, 0.45, 0.55, 0.85 and 1 have been grown from In self-flux and characterized by x-ray diffraction and microprobe analysis. Starting from the antiferromagnet Ce 2 RhIn 8 , the Néel temperature gradually decreases with increasing Pd concentration and the antiferromagnetism has disappeared for x ≥0.45. Superconductivity has been observed only for Ce 2 PdIn 8 . [ABSTRACT FROM AUTHOR]

Thermoelectric effects are one of the promising ways to utilize waste heat. Novel approaches have appeared in recent decades aiming to enhance thermoelectric conversion. The theory of energy filtering of free carriers by inclusions is among the latest developed methods. Although the basic idea is clear, experimental evidence of this phenomenon is rare. Based on this concept, we searched suitable systems with stable structures showing energy filtering. Here, we report on the anomalous behavior of Cr-doped single-crystal Bi 2 Se 3 that indicates energy filtering. The solubility of chromium in Bi 2 Se 3 was studied, which is the key parameter in the formation process of inclusions. We present recent results on the effect of Cr-doping on the transport coefficients on a wide set of single crystalline samples. Magnetic measurements were used to corroborate the conclusions drawn from the transport and X-ray measurements. [ABSTRACT FROM AUTHOR]

We report on single crystal growth and crystallographic parameters results of Ce2PdIn8, Ce3PdIn11, Ce2PtIn8 and Ce3PtIn11. The Pt-systems Ce2PtIn8 and Ce3PtIn11 are synthesized for the first time. All these compounds are member of Ce n T m In3n+2m (n=1, 2,..; m=1, 2,.. and T= transition metal) to which the extensively studied heavy fermion superconductor CeCoIn5 belongs. Single crystals have been grown by an In self-flux method. Differential scanning calorimetry studies were used to derive optimal growth conditions. Evidently, the maximum growth conditions for these materials should not exceed 750°C. Single crystal x-ray data show that Ce2 TIn8 compounds crystallize in the tetragonal Ho2CoGa8 phase (space group P4/mmm) with lattice parameters a=4.6898(3)Å and c=12.1490(8)Å for Pt-based one (Pd: a=4.6881(4)Å and c=12.2031(8)Å). Ce3 TIn11 compounds adopt Ce3PdIn11 structure with a=4.6874(4)Å and c=16.8422(12)Å for Pt-based one (Pd: a=4.6896Å and c=16.891Å). Specific heat experiments on Ce3PtIn11 and Ce3PdIn11 have revealed that both compounds undergo two successive magnetic transitions at T 1 ~2.2K followed by T N ~2.0K and T 1 ~1.7K and T N ~1.5K, respectively. In addition, both compounds exhibit enhanced Sommerfeld coefficients yielding γ Pt=0.300J/molK2 Ce (γ Pd=0.29J/molK2 Ce), hence qualifying them as heavy fermion materials. [ABSTRACT FROM AUTHOR]

Abstract: We have used the magnetocaloric effect (MCE) to investigate the modifications of the cluster-glass transitions detected at temperatures above the ferromagnetic ground state in some representative compositions . The MCE was calculated from heat-capacity data measured in fields up to 90kOe and temperature down to 500mK. The observed evolution of MCE along the series is discussed considering hybridization effects. [Copyright &y& Elsevier]