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Register a new userGeneration of Spin Currents in the Skyrmion Phase of a Helimagnetic Insulator $mathrm{Cu_2OSeO_3}$
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We report spin-current generation related with skyrmion dynamics resonantly excited by a microwave in a helimagnetic insulator $mathrm{Cu_2OSeO_3}$. A Pt layer was fabricated on $mathrm{Cu_2OSeO_3}$ and voltage in the Pt layer was measured upon magnetic resonance of $mathrm{Cu_2OSeO_3}$ to electrically detect injected spin currents via the inverse spin Hall effect (ISHE) in Pt. We found that ISHE-induced electromotive forces appear in the skyrmion phase of $mathrm{Cu_2OSeO_3}$ as well as in the ferrimagnetic phase, which shows that magnetic skyrmions can contribute to the spin pumping effect.
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We propose and demonstrate spin manipulation by magnetically controlled modulation of pure spin currents in cobalt/copper lateral spin valves, fabricated on top of the magnetic insulator Y$_3$Fe$_5$O$_{12}$ (YIG). The direction of the YIG magnetization can be controlled by a small magnetic field. We observe a clear modulation of the non-local resistance as a function of the orientation of the YIG magnetization with respect to the polarization of the spin current. Such a modulation can only be explained by assuming a finite spin-mixing conductance at the Cu/YIG interface, as it follows from the solution of the spin-diffusion equation. These results open a new path towards the development of spin logics.
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