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The benzene ring vibrational motion in poly(phenylenevinylene) has been studied by 1H nuclear magnetic resonance (NMR) measurements. By employing a simple model of the out-of-plane phenylene oscillation giving rise to a change in the dipolar splitting of the 1H NMR line shape, the oscillation angle of the benzene ring was obtained as a function of temperature. [ABSTRACT FROM AUTHOR]

We investigate the spin Hall magnetoresistance (SMR) in niobium (Nb) attached to Y3Fe5O12 near the superconducting critical temperature ( Tc) of Nb. The SMR vanishes after cooling the sample below Tc, and recovers if the temperature is raised. When a magnetic field larger than the critical field of Nb is applied, the SMR re-emerges with an enhanced magnitude even if the temperature is below Tc. The experimental results demonstrate that the SMR could be completely suppressed by the coupling between superconducting condensation and spin-orbit interaction in superconductors. In addition to the fundamental physics on the charge-spin interactions in superconductors, our work adds a different dimension to superconducting spintronics. (© 2015 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Crystal order is not restricted to the periodic atomic array, but can also be found in electronic systems such as the Wigner crystal or in the form of orbital order, stripe order and magnetic order. In the case of magnetic order, spins align parallel to each other in ferromagnets and antiparallel in antiferromagnets. In other, less conventional, cases, spins can sometimes form highly nontrivial structures called spin textures. Among them is the unusual, topologically stable skyrmion spin texture, in which the spins point in all the directions wrapping a sphere. The skyrmion configuration in a magnetic solid is anticipated to produce unconventional spin–electronic phenomena such as the topological Hall effect. The crystallization of skyrmions as driven by thermal fluctuations has recently been confirmed in a narrow region of the temperature/magnetic field (T–B) phase diagram in neutron scattering studies of the three-dimensional helical magnets MnSi (ref. 17) and Fe1−xCoxSi (ref. 22). Here we report real-space imaging of a two-dimensional skyrmion lattice in a thin film of Fe0.5Co0.5Si using Lorentz transmission electron microscopy. With a magnetic field of 50–70 mT applied normal to the film, we observe skyrmions in the form of a hexagonal arrangement of swirling spin textures, with a lattice spacing of 90 nm. The related T–B phase diagram is found to be in good agreement with Monte Carlo simulations. In this two-dimensional case, the skyrmion crystal seems very stable and appears over a wide range of the phase diagram, including near zero temperature. Such a controlled nanometre-scale spin topology in a thin film may be useful in observing unconventional magneto-transport effects. [ABSTRACT FROM AUTHOR]

In high temperature superconducting (HTS) transformer with double pancake windings, the perpendicular component of leakage magnetic flux density (Br) applied to HTS tapes of double pancake windings is larger than that of solenoid windings, which acts as a cause to decrease the critical current in HTS tape and increase AC loss. In this paper, in order to reduce the Br applied to HTS windings, the use of ferrite flux diverters is presented. Flux diverters are located in between the primary windings and the secondary windings, and must be made of low-loss materials to minimize the heat. And electromagnetic analysis of a single-phase 1 MVA 22.9 kV/6.6 kV HTS transformer with flux diverters in HTS windings was accomplished. The variation of Br applied to the secondary windings and magnetic flux density in flux diverters were analyzed by changing their relative permeability of flux diverters respectively. Suitable relative permeability of flux diverters to reduce Br applied to HTS windings was selected, considering flux diverter losses by increment of B in flux diverters. [ABSTRACT FROM AUTHOR]

The spin Hall effect and the magnetic proximity effect are two main sources of the magnetoresistance (MR) effects in heavy metal/ferromagnet bilayers, where they play isolated roles but are usually contaminated by each other. In Ta1-xPtx/YIG(=Y3Fe5O12) bilayers consisting of Ta and Pt nanograins, these effects are intrinsically coupled to generate new MR with 360° direction sensitivity to the magnetic field and proportionality to the out-of-plane magnetization of YIG. Due to the opposite spin Hall angle of Ta and Pt, vertical spin accumulation is generated via the spin Hall effect at the transverse boundaries between Ta and Pt grains. The spin-dependent scattering by the proximity-induced Pt magnetization finally leads to the MR, which is named as vertical spin Hall MR taking the role of spin Hall angle into account. Besides fundamental insight to spin transport physics, our work provides an approach to detecting perpendicular magnetization in a variety of magnets. [ABSTRACT FROM AUTHOR]