Dicationic magnetic ionic liquids with heteroanionic anions allow for tunability of physicochemical properties while retaining magnetic susceptibility.

We observe amplification of spin-wave packets propagating along a film of single-crystal yttrium iron garnet subject to a transverse temperature gradient. The spin waves are excited and detected with standard techniques used in magnetostatic microwave delay lines in the 1-2 GHz frequency range. The amplification is attributed to the action of a thermal spin-transfer torque acting on the magnetization that opposes the relaxation and which is created by spin currents generated through the spin-Seebeck effect. The experimental data are interpreted with a spin-wave model that gives an amplification gain in very good agreement with the data.

We demonstrate that spin waves propagating in a film of yttrium iron garnet (YIG) can be amplified by a dc current in an adjacent Pt layer by means of the spin Hall effect. The experiments are done at room temperature using pulsed currents to avoid sample heating. Amplification occurs only for surface like modes propagating in a direction perpendicular to the applied in-plane field. The results are interpreted with a model for spin-wave propagation in a YIG film with magnetic losses and subject to a spin-transfer torque due to spin currents created by the spin Hall effect in the Pt layer.

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This paper shows a study of Nanocomposite formed by adding reduced Graphene oxide with high acidity and polystyrene. The interest and research in the material is due to the ability of these nanoparticles significantly altering the electrical and mechanical properties of the polymer, even addition of small levels. The existence of functional groups on the graphene oxide containing abundant oxygen such as; epoxy, hydroxyl and carboxylic acid, can be well dispersed in the polymer because of its good interaction with polymer chains. In this study we used the solution by dispersing method to that made the use of solvent tetrahydrofuran (THF), for purposes of obtaining a reaction with functionalization of graphene oxide / polystyrene in time of 48 hours. The analyses of physical-chemical characterizations were made diffraction X-ray (XRD), scanning electron microscopy (SEM), Infrared Spectroscopy (IRD), Thermogravimetric Analysis (TG) and Differential calorimeter by scanning (DSC). The results obtained by XRD diffraction pattern showed a strong expansion in the peak, indicating amorphization on single sheets of graphene oxide due to distorted sp 3 sites CO. The morphology of the nanocomposite structure was with surface roughness, folds and rough predominant oxidation process of oxygenated functional groups. Their techniques showed the range of absorption, crystallinity degree and the mass loss. Finally, current and future possible applications of formed polystyrene nanocomposite/ graphene oxide show high acidity efficiency in the use of thin films.