Current-Induced Microwave Excitation of a Domain Wall Pinned in a Magnetic Wire with Bi-Axial Anisotropy

  title={Current-Induced Microwave Excitation of a Domain Wall Pinned in a Magnetic Wire with Bi-Axial Anisotropy},
  author={Katsuyoshi Matsushita and Jun Sato and Hiroshi Imamura},
  journal={Journal of the Physical Society of Japan},
We studied the current-induced magnetization dynamics of a domain wall pinned geometrically in a magnetic wire with bi-axial anisotropy. We showed that above the threshold current density, breathing-mode excitation, where the thickness of the domain wall oscillates, is induced by spin-transfer torque. We found that the breathing-mode can be applied as a source of microwave oscillation because the resistance of the domain wall is a function of the domain wall thickness. In a current sweep… 
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