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Self-propagating formation reactions have been studied in multilayer foils and they are currently being investigated for applications in joining and ignition. Here, we introduce a reactive multilayer foil which contains a reduction-oxidation thermite reaction between CuO[sub x] and Al. Typically in reactive multilayer foils, elemental layers react and form a single intermetallic product. In this thermite reaction, however, aluminum and copper oxide are, respectively, oxidized and reduced and form aluminum oxide and copper. The fully dense multilayer foils provide a well-defined geometry for studying the thermodynamics, kinetics, and intermediate phase formation in the CuO[sub x]/Al thermite reaction. Here, sputter deposition of CuO[sub x]/Al multilayer foils is demonstrated, and x-ray diffraction and transmission electron microscopy, including high resolution transmission electron microscopy and electron spectroscopic imaging, are used to characterize the as-deposited foil and the final products. The heat released in the reaction is quantified using differential thermal analysis, and the velocity of the self-propagating reaction is reported. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Pr3In exhibits an antiferromagnetic transition at ∼12 K. This transition appears to occur due to the exchange-generated admixture of higher lying crystal field levels into the singlet ground state. It is thus an example of an induced moment antiferromagnet. To provide detailed understanding of the magnetic behavior of Pr3In, we have measured the magnetic excitation spectrum with inelastic neutron scattering experiments. We observe a clear dispersion of a crystal field excitation at 4 K. Above 100 K, the dispersion of the crystal field excitation has largely vanished and a crystal field scheme for Pr in a cubic site symmetry (in which the lowest states are a Γ1 singlet and a Γ4 triplet) provides a good approximation to the data. [ABSTRACT FROM AUTHOR]

The crystalline electric field (CEF) energy level scheme of the heavy fermion superconductor CeCoIn5 has been determined by means of inelastic neutron scattering (INS). Peaks observed in the INS spectra at ∼8 and ∼27 meV with incident neutron energies between Ei=30 and 60 meV and at a temperature T=10 K correspond to transitions from the ground state to the two excited states, respectively. The wave vector and temperature dependence of these peaks are consistent with CEF excitations. Fits of the data to a CEF model yield the CEF parameters B20=-0.80 meV, B40=0.059 meV, and |B44|=0.137 meV corresponding to an energy level scheme: Γ7(1)(0)[=0.487|±5/2>-0.873|∓3/2>], Γ7(2)(8.6 meV,100 K), and Γ6(24.4 meV,283 K). © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Investigates the low-temperature resistivity of Ce[sub0.9-x]La[subx]Th[sub0.1] alloys. Experimental results; Residual resistivity of the alloys.

Presents an abstract of the article 'Neutron scattering studies of the dynamic susceptibility in the mixed-valent alloy Ce[sub1-x]Th[subx] at high energy,' by C.-K. Loong, B.H. Grier. S.M. Shapiro, J.M. Lawrence, R.D. Parks and S.K. Sinha.

The crystalline electric field (CEF) energy level scheme of the heavy fermion superconductor CeCoIn5 has been determined by means of inelastic neutron scattering (INS). Peaks observed in the INS spectra at ∼8 and ∼27 meV with incident neutron energies between Ei=30 and 60 meV and at a temperature T=10 K correspond to transitions from the ground state to the two excited states, respectively. The wave vector and temperature dependence of these peaks are consistent with CEF excitations. Fits of the data to a CEF model yield the CEF parameters B20=-0.80 meV, B40=0.059 meV, and |B44|=0.137 meV corresponding to an energy level scheme: Γ7(1)(0)[=0.487|±5/2>-0.873|∓3/2>], Γ7(2)(8.6 meV,100 K), and Γ6(24.4 meV,283 K). © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]