1 / 10

Influence of large currents on the magnetization dynamics of ferromagnetic metals

Influence of large currents on the magnetization dynamics of ferromagnetic metals. J. Fernandez-Rossier , M. Braun and A. H. MacDonald Department of Physics, University of Texas at Austin. Current flow: How does it affect Magnetization dynamics ?. Magnetization controls

juliet
Download Presentation

Influence of large currents on the magnetization dynamics of ferromagnetic metals

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Influence of large currents on the magnetization dynamics of ferromagnetic metals J. Fernandez-Rossier, M. Braun and A. H. MacDonald Department of Physics, University of Texas at Austin Current flow: How does it affect Magnetization dynamics ? Magnetization controls current flow (GMR, TMR) March Meeting 2003, Austin (TX)

  2. Current driven spin wave instability • Y. Ji, C.L. ChienCond-mat/0210116 • M. Tsoi et al. E.B. Myers et al.,Science 285, 867 (1999).

  3. Bazaliy, Jones, Zhang. Fully polarized s-d model: Current • Valid for ALL metallic ferromagnets: Spin Current • Enhanced Spin Wave Damping: Dynamics: Landau-Lifshitz <-> spin waves This work:

  4. Our model • Hubbard Model • Itinerant d electrons • Partially polarized electrons • Generalize to LDSA

  5. q Ground state: Spin split bands Spin waves. No current No current Spin wave= Linear combination e-h pairs

  6. Current q Spin waves with current Total current: Spin current:

  7. Remarks • The extra term modifies the off-diagonal terms • in the action • Similar term in super-fluids with super-current • Microscopic derivation • Unrelated to Spin Torque

  8. eV) m ( w Spin Wave Damping Spin waves for iron 4 Gilbert Damping 2 Two magnon damping Two magnon damping 0 0 2 4 6 8 10 q (m-1)

  9. Conclusions • Spin wave spectrum of current driven ferromagnetic metals • Enhanced Damping Email: joaquin@physics.utexas.edu

  10. d EF D.O.S. D.O.S. Spin waves in the Hubbard model • Hubbard model: • Partially polarized • itinerant d-electrons

More Related