Search

Microwave spin pumping at ferromagnetic resonance from ferromagnetic films into nonmagnetic films is an efficient method to realize spin injection. The spin injection efficiency is proportional to the spin mixing conductance and can be detected by measuring voltages converted from spin current via the inverse spin Hall effect. In this work, we modified the properties of the ferromagnetic layer by thermal annealing. The results show that the crystal quality of the ferromagnetic films, as well as the magnetic properties has been greatly modified while the spin mixing conductance is insensitive to it. The work represent an incentive to work on engineering the spin Hall angle of the nonmagnetic layer to improve the spin Hall effect or the inverse spin Hall effect. [ABSTRACT FROM AUTHOR]

Electronic structures of Rh 2 TMSn (TM = Cr, Mn, Fe, Co, Ni and Cu) full Heusler compounds are calculated by the state-of-the-art electronic structure codes with the local density approximation aiming to understand the structure instability microscopically. The instability of the compounds can be explained by the band Jahn–Teller effect. The compounds can be categorized into two groups: In the first group, the density of states at the Fermi level are contributed mainly from Rh, while in the rest, both the Rh and TM atoms contribute. The high density of states at the Fermi level of the first group compounds may be smoothed and the highly symmetric phase is stable as found in experiments. The compounds in the second group tetragonally distort according to our calculation and was found in the experiments. [ABSTRACT FROM AUTHOR]

Abstract: Barium ferrite films were prepared by spin-coating of gels on sapphire (00 l) faces. Ethylenediaminetetraacetic acid was used to bind the metal ions. Thin films prepared by this method show faceted hexagonal grains with c-axis normal to the film plane and [110]sapphire ||[100]film. Needle-like grains, which have c-axis in the film plane, are minimized. Epitaxial growth of the film can be observed by the high resolution images. Reduction of the a and c-axis of the film compared with those of the bulk materials is confirmed both in real space and reciprocal space. Magnetic hysteresis loops were recorded in-plane and out-of-plane. The film shows uniaxial anisotropy as exemplified by branched domains with coercivity field of 87.6kA/m along the in-plane direction and of 302.5kA/m along the out-of-plane direction. [Copyright &y& Elsevier]

Flexible supercapacitors have attracted great attention owing to some advantages of flexibility, light weight and high-power output, and have displayed enormous potential in wearable electronic devices. However, the hydrogel electrolyte in flexible supercapacitors usually shows insufficient mechanical properties and low ionic conductivity under harsh environments, making it unsatisfactory for practical applications. Herein, a novel polyacrylamide/montmorillonite/ionic liquid-Li 2 SO 4 hydrogel electrolyte with wide temperature tolerance, high ionic conductivity and super-stretchable ability is prepared via facile thermally initiated radical polymerization. The layered montmorillonite can not only improve the thermal stability of the hydrogel, but also form a conductive channel to promote the rapid transport of ions. Moreover, the introduction of ionic liquid into the hydrogel can further increase the working temperature range. In consequence, the polyacrylamide/montmorillonite/ionic liquid-Li 2 SO 4 hydrogel electrolyte exhibits outstanding stretch ability (tensile strain over 1000%), high ionic conductivity (41.7 and 50.7 mS cm-1 at 25 °C and 40 °C, respectively). In addition, supercapacitor with the polyacrylamide/montmorillonite/ionic liquid-Li 2 SO 4 hydrogel electrolyte has good electrochemical property within the wide temperature tolerance from − 10–80 °C. [Display omitted] • A novel hydrogel electrolyte (PAM/MMT/EMIMBF 4 -Li 2 SO 4) is prepared by easy method. • The hydrogel with porous structure has good twist, compress and stretch performance. • As electrolyte the hydrogel shows excellent ionic conductivity and thermal stability. • Supercapacitor with the hydrogel electrolyte possesses good electrochemical properties. [ABSTRACT FROM AUTHOR]