Magnetic devices

Magnetic domain wall manipulation
Substantial critical current density is required for current-driven switching in patterned magnetic devices, giving rise to an ambiguity in the interpretation using joule heating and/or spin-transfer torque effect alone. Thus, we have attempted to identify these possible mechanisms by adopting a notched magnetic multilayer strip and introduce high ambient temperature and/or high dc current density. The device consists of one micron wide of Ni80Fe20-5nm/Cu-2.5nm/Ni80Fe20-25nm and Ni80Fe20-25nm /Cu-7.0nm/ Ni80Fe20-5nm tri-layer pseudo spin valve strip with 0.5 μm width of symmetrical notch in the middle. The low field differential MR curves are measured at various ambient temperatures and with various dc currents at room temperature. Notice that the MR curves reveal extra switching in the soft layer with DC current density above 1.54×1011A/m2, whereas the MR curves maintain single switching at ambient temperatures up to 323 K. A comparison between the ambient temperature and Joule heating has led to a better understanding in resolving the key mechanism for magnetization reversal in the patterned devices.

MagneticDomainWall

Other magnetic device related publications

  • Fabrication and characterization of microscaled on-chip toroidal inductors
    J. Y. Ou    , S. H. Chen, H. M. Lee, J. C. Wu
    IEEE Transactions on Magnetics 45 (10), 4767 (2010) doi:10.1109/TMAG.2009.2023916
  • Current driven magnetization reversal in microstructured spin valve with current-in-plane configuration
    C. Y. Kuo, C. T. Chao, J. Y. Ou, L. Horng, J. C. Wu, T. H. Wu, M. Tsunoda and M. Takahashi
    Journal of Applied Physics 105 (7), 07D118 (2009) doi: 10.1063/1.3068483
  • A Novel Bottom-Up Fabrication Process for Controllable Sub-100 nm Magnetic Multilayer Devices
    M. Y. Kao, J. Y. Ou, L. Horng, J. C. Wu
    IEEE Transactions on Magnetics 44 (11), 2734-2736 (2008) doi:10.1109/TMAG.2008.2001502
  • Layer-and lateral-resolved magnetization studies using photoemission electron microscopy
    D. H. Wei, Y. J. Hsu, C. C. Lin, C. H. Lai, J. Y. Ou, J. C. Wu
    Journal of magnetism and magnetic materials 282, 49-52 (2004) doi:10.1016/j.jmmm.2004.04.01