Current-induced magnetization dynamics in nanomagnet

Teruo Ono

Institute for Chemical Research, Kyoto University, Uji 611-0011, Japan

The manipulation of magnetization by spin currents is a key technology for future spintronics. The underlying physics is that spin currents can apply a torque on the magnetic moment when the spin direction of the conduction electrons has a relative angle to the local magnetic moment. This leads us to a general concept that any type of spin structure with spatial variation can be excited by a spin-polarized current in a ferromagnet. We confirmed this concept for two typical noncollinear spin structures: magnetic domain wall (DW) [1]-[5] and magnetic vortex [6], [7].

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