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Inelastic neutron scattering (INS) was used for determining the crystalline electric field (CEF) energy level scheme of the heavy fermion superconductor CeCoIn5. The orbital fluctuations contributing to superconductivity are affected by the shape of the f orbitals under the influence of the CEF.

Abstract: Temperature dependencies of the nuclear spin-relaxation rate and specific heat of PuCoGa5 and isostructural PuRhGa5 are consistent with their superconductivity being unconventional. A simple model of hybridization between localized f-electrons and itinerant conduction-band electrons gives a framework for interpreting basic similarities and differences between these Pu-based superconductors and their Ce-based analogs. This model also provides a rationale for the correlation between T c and a characteristic spin-energy scale in these materials. [Copyright &y& Elsevier]

Develops an ozone trapping system designed for safe and consistent delivery to a reaction vessel. Use of silica gel to trap the ozone; Significance of using silica gel; Observation of the absence of liquid baths in the trapping system.

Abstract: We report 235U and 121Sb NMR in the antiferromagnetic state of . Our spectra agree with previous reports by Kato et al., however, we find evidence to suggest three distinct magnetic environments. The temperature dependence of the Sb spin lattice relaxation rate reveals a crossover to Korringa-like metallic behavior below 7K. We interpret this behavior as arising from conduction electrons scattering below the magnon excitation gap. [Copyright &y& Elsevier]

Abstract: We present an In(1) NQR study on the heavy-fermion (HF) compound CeCo(In1−x Cd x )5 . Bulk measurements indicate that Cd doping acts as an electronic tuning agent in CeCoIn5, and that superconductivity (SC) and antiferromagnetism (AFM) may coexist at ambient pressure for . For , the nuclear spin lattice relaxation rate shows a broad peak at the Néel temperature , with a subsequent onset of SC at . Our results provide strong evidence for microscopic coexistence of these two ground states. The nuclear magnetization recovery curves in both the ordered and mixed states reveal a single -component, which suggests a homogeneous nature of the Ce-4f1 electronic state. [Copyright &y& Elsevier]

Abstract: Experiments that probe the normal and superconducting states of the heavy-fermion compounds CeMIn5, Mr, consistently point to the dependence of superconductivity on magnetism and, consequently, to the conclusion that soft magnetic excitations produce Cooper pairing. A more limited number of experiments on the isostructural superconductors PuMGa5, Mlso are consistent with a magnetic pairing mechanism, but in these cases, the relationship between magnetism and superconductivity is less obvious. A connection between the Ce- and Pu-based families of unconventional superconductors is provided through a common dependence of their superconducting transition temperatures on lattice anisotropy and a weak structural distortion that may reflect a hybridization-induced change in magnetic fluctuations. [Copyright &y& Elsevier]