Low-Electric-Current-Driven Spin Dynamics
Yi-Chien weng1,2*, C.-T. Liang1, J. G. Lin2
1Graduate Institute of Applied Physics, National Taiwan University, Taipei, Taiwan
2Center for Condensed Matter Sciences, National Taiwan University, Taipei, Taiwan
* Presenter:Yi-Chien weng
From an application-oriented viewpoint, using a low charge current to produce a pure spin current could effectively reduce the heating effect of an electronic system. From a physicist’s point of view, the current effect on magnetization dynamics by monitoring the linewidth of a ferromagnetic resonance (FMR) spectrum is interesting. In this work, we apply a DC current on a Cobalt (Co)/Platinum (Pt) bilayer with the thickness being 10 nm for each layer and the sample size about 3 mm×1.5 mm. The spin current is produced in the Pt layer with spin Hall effect and flows into the Co layer to manipulate its magnetization. We monitor the FMR spectra with changing the applied current from 0 to 160 mA and obtain the current dependent linewidth and the damping constant. The spin Hall angle is estimated to be 0.037 for our Co/Pt bilayer based on the analysis of damping constant, which is comparable to that calculated from the spin pumping method [1, 2].

[1] K. Ando, S. Takahashi, K. Harii, K. Sasage, J. Ieda, S. Meakawa, and E. Saitoh, Phys. Rev. Lett. 101, 036601 (2008).
[2] J.-C. Rojas-Sanchez, N. Reyren, P. Laczkowski, W. Savero, J.-P. Attane, C. Deranlot, M. Jamet, J.-M. George, L. Vila, and H. Jaffers, Phys. Rev. Lett. 112, 106602 (2014).

+This work is financially supported by the Ministry of Science & Technology of R. O. C. under the grand no. MOST 105-2112-M-002-010-MY3.

Keywords: spin Hall angle , ferromagnetic resonance, spintronics