Magnetization Dynamics under Spin Current

Yoshihiko Togawa^a,b, Takashi Kimura^c, Ken Harada^d, Tetsuya Akashi^e, Akira Tonomura^b,d and Yoshichika Otani^b,f

^aNanoscience and Nanotechnology Research Center, Osaka Prefecture University
^bAdvanced Research Institute, Instisute of Physical and Chemical Research (RIKEN)
^cInamori Frontier Research Center, Kyushu University
^dHitachi Ltd.
^eHitachi High-Technologies Co.
^fInstitute for Solid State Physics, the University of Tokyo

Abstract: Magnetization dynamics driven by spin current in nano-scaled ferromagnetic materials has attracted much attention in academic and industrial viewpoints because of a wide variety of promising applications in magnetic recording and spintronic devices with higher integration density and lower energy consumption. In the manuscript, basic concepts of spin current and its interaction with magnetization are introduced. TEM in-situ analysis method using Lorentz microscopy and electron holography together with transport measurement has great advantages in microscopically clarifying spintronic properties. Making full use of these advantages, manipulation of magnetic domain states using spin current under small magnetic fields is demonstrated. Its application in spintronic devices and future prospect of spintronic investigation using TEM in-situ analysis method are discussed.

Key words: Spin current, Magnetic domain dynamics, TEM in-situ observation, Electron holography, Lorentz microscopy