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Proximity effect between superconductors and ferromagnets may become long range due to the generation of triplet pairs. The recent finding of a long one micron-range unconventional Josephson effect between YBa2Cu3O7 High Tc cuprates separated by a half metallic La0.7Sr0.3MnO3 manganite ferromagnet has uncovered a novel unconventional triplet proximity effect. In this paper we examine the temperature dependence of the critical current of planar Josephson junctions. We find that the critical current –normal resistance product follows the predictions of traditional superconductor-normal metal-superconductor junctions which implies that triplet pairs in a ferromagnet are transported in the diffusive limit similarly to singlet pairs in a normal metal. This result calls for theoretical studies of the new triplet Josephson effect and underlines its potential in future superconducting spintronics.

The inelastic response from liquid deuterium has been measured on a thermal three-axis neutron spectrometer at two different temperatures. The observed neutron scattering spectra show clear inelastic features which have been analysed using a damped harmonic oscillator (DHO) model. The momentum transfer dependences of the DHO frequencies and damping coefficients at each temperature are compared and related to the results of the correlated density matrix formalism.

Residual strains were measured in the ferrite phase of pearlitic steel rods along the radial, axial and hoop directions. Two samples with different initial diameters were subjected to one drawing pass (using same drawing parameters) with 20% section reduction and measured in two different neutron diffraction instruments. The results show that the residual strain state is very similar in both cases, regardless of the diameter of the initial rod. This means that the final residual strain-stress state is unique and it is related to the cold-drawing process parameters. In addition, the results show the reliability of strain scanning with different neutron instruments and experimental conditions.

The magnetic and structural dynamics in liquid oxygen are studied by means of high-resolution inelastic neutron scattering and computer molecular-dynamics simulations. The former technique enables an approximate separation between nuclear and magnetic responses from the total, unpolarized neutron double differential cross-sections. The magnetic scattering spectra are then shown to reproduce the wave vector dependence of the inelastic intensities associated with the magnetic excitations measured in a previous study. Finally, the magnetic spectral functions are shown to be well reproduced by a model of exchange-coupled paramagnet and estimates of the exchange parameter and correlation length are obtained from the analysis of the frequency moments.

The excitations below 40 meV of a glass-former mixture (CD3OD 6% D2O) have been studied by neutron spectroscopy. A well-resolved inelastic peak with a dispersion behaviour reminiscent of those found in metallic glasses has been observed for temperatures above 10 K. The presence of such peak is correlated with an abrupt enhancement of the total vibrational density of states (TDOS). The nature of the excitations is analysed by means of their wave vector dependence. Finally, the TDOS are tentatively interpreted in terms of a coupling between sound waves and localized excitations, which becomes effective for temperatures above 10 K.

The inelastic neutron scattering spectra of liquid sulphur dioxide have been measured for two thermodynamic states and for the momentum-transfer range 0.35

The authors briefly describe the results of a neutron scattering study on the dynamics of liquid oxygen (T=55.0 K,p=2 bar), performed at a temperature just above the melting point. The wavevector dependence of the inelastic intensities shows a pronounced feature of magnetic origin centred at Q=1.2 AA-1 ('zone boundary') reminiscent of those found in the solid beta -phase. These indicate a dynamical antiferromagnetic (AF) interaction in liquid oxygen at a temperature of approximately 2TN (TN approximately=30 K for solid alpha -phase). The AF coupling extends over only a very short range ( approximately=5.2 AA) and an energy scale of between 0.7 and 3 THz.

Medium- ( Delta E=50 mu eV) and high-resolution ( Delta E=15 mu eV) neutron quasi-elastic scattering spectra of liquid CCl4 at two temperatures within the liquid range are reported. The (mostly coherent) dynamical structure factors are analysed in terms of a model which takes into account the effects of the liquid structure on the single-particle dynamics, and extends the usual rotational diffusion approximations. Such an extension was found to be necessary in order to reconcile the measured dynamical parameters with those available from NMR relaxation.