Details

Autor(en) / Beteiligte

• Guo, J.H.
• Xia, J.
• Zhang, X.C.
• Pong, Philip W.T.
• Wu, Y.M.
• Chen, H.
• Zhao, W.S.
• Zhou, Y.

Titel

A ferromagnetic skyrmion-based nano-oscillator with modified profile of Dzyaloshinskii-Moriya interaction

Ist Teil von

• Journal of magnetism and magnetic materials, 2020-02, Vol.496, p.165912, Article 165912

Ort / Verlag

Amsterdam: Elsevier B.V

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •The unique layered model induces two Dzyaloshinskii-Moriya interaction areas.•Skyrmion’s stable motion can happen on the ferromagnetic nanodisk of this model.•The ferromagnetic skyrmion STNO has good performances on frequency and linewidth.•The effects of current density, radius and damping have been also discussed. Magnetic skyrmions have attracted great interest in recent years due to their potential wide-scale applications in spintronic devices, such as the spin torque nano-oscillator (STNO) and racetrack memory. The spin-transfer torque can drive the motion of skyrmions on a ferromagnetic nanodisk, where skyrmions are stabilized by the Dzyaloshinskii-Moriya interaction (DMI). However, the Magnus force acted on a skyrmion can drive the skyrmion moving toward either the nanodisk center or edge, which may lead to the destruction of skyrmion at edge, and thus reduce the performance of skyrmion-based STNO. In order to overcome this problem, we designed a ferromagnet/spacer/ferromagnet/heavy metal STNO model, in which the inner and outer areas of the ferromagnetic nanodisk have different DMI, and those skyrmions could move along the boundary between inner and outer areas. We investigated the dynamics of skyrmions in such a STNO model by adjusting several geometrical and material parameters. We obtained an optimal frequency of skyrmion oscillation of 3.43 GHz. Our results may be useful for designing future STNOs based on skyrmions, where the Magnus-force-induced destruction of skyrmions can be effectively avoided.