1,382 research outputs found
Current-Induced Resonant Motion of a Magnetic Vortex Core: Effect of Nonadiabatic Spin Torque
The current-induced resonant excitation of a magnetic vortex core is
investigated by means of analytical and micromagnetic calculations. We find
that the radius and the phase shift of the resonant motion are not correctly
described by the analytical equations because of the dynamic distortion of a
vortex core. In contrast, the initial tilting angle of a vortex core is free
from the distortion and determined by the nonadiabaticity of the spin torque.
It is insensitive to experimentally uncontrollable current-induced in-plane
Oersted field. We propose that a time-resolved imaging of the very initial
trajectory of a core is essential to experimentally estimate the
nonadiabaticity.Comment: 4 pages, 4 figure
Prediction of Giant Spin Motive Force due to Rashba Spin-Orbit Coupling
Magnetization dynamics in a ferromagnet can induce a spin-dependent electric
field through spin motive force. Spin current generated by the spin-dependent
electric field can in turn modify the magnetization dynamics through
spin-transfer torque. While this feedback effect is usually weak and thus
ignored, we predict that in Rashba spin-orbit coupling systems with large
Rashba parameter , the coupling generates the spin-dependent
electric field [\pm(\alpha_{\rm R}m_e/e\hbar) (\vhat{z}\times \partial
\vec{m}/\partial t)], which can be large enough to modify the magnetization
dynamics significantly. This effect should be relevant for device applications
based on ultrathin magnetic layers with strong Rashba spin-orbit coupling.Comment: 4+ pages, 2 figure
Soil Washing of Fluorine Contaminated Soil Using Various Washing Solutions
Bench-scale soil washing experiments were conducted to remove fluoride from contaminated soils. Five washing solutions including hydrochloric acid (HCl), nitric acid (HNO3), sodium hydroxide (NaOH), sulfuric acid (H2SO4) and tartaric acid (C4H6O6) were tested. The concentration of the washing solutions used ranged from 0.1 M to 3 M with a liquid to solid ratio of 10. The soil washing results showed that the most effective washing solution for the removal of fluoride from contaminated soils was HCl. The highest fluoride removal results of approximately 97% from the contaminated soil were obtained using 3M HCl. The fluoride removal efficiency of the washing solution increases in the following order: C4H6O
Spin-wave propagation in the presence of inhomogeneous Dzyaloshinskii-Moriya interactions
We theoretically investigate spin-wave propagation through a magnetic metamaterial with spatially modulated Dzyaloshinskii-Moriya interaction. We establish an effective Schrodinger equation for spin waves and derive boundary conditions for spin waves passing through the boundary between two regions having different Dzyaloshinskii-Moriya interactions. Based on these boundary conditions, we find that the spin wave can be amplified at the boundary and the spin-wave band gap is tunable either by an external magnetic field or the strength of Dzyaloshinskii-Moriya interaction, which offers a spin-wave analog of the field-effect transistor in traditional electronics.112sciescopu
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