AVS 45th International Symposium
    Magnetic Interfaces and Nanostructures Technical Group Friday Sessions
       Session MI-FrM

Invited Paper MI-FrM1
Magnetization Dynamics: A Study of the Ferromagnet/Antiferromagnet Interface and Exchange Biasing

Friday, November 6, 1998, 8:20 am, Room 324/325

Session: Magnetization Dynamics and Magneto-Optics
Presenter: R.E. Camley, University of Colorado, Colorado Springs
Correspondent: Click to Email
We use a method which employs a dynamic calculation of magnetization motion to find both the static configuration and the spin wave excitations in a ferromagnet/antiferromagnet layered structure. Our results for the static structure are similar to those found in Koon's model; i.e. in zero applied field the ferromagnet points perpendicularly to the easy axis of the antiferromagnet, and the surface spins of the antiferromagnet are in a surface spin flop configuration. The calculated hysteresis curve for this structure shows a small exchange bias, in agreement with typical experimental results. We explore how this bias depends on the parameters of the antiferromagnet and on the nature of the interface coupling. The spin wave modes are developed using the same simple model. The frequency of the lowest spin wave in the ferromagnet shows a dramatic dip when the ferromagnet spins begin to rotate - where the hysteresis curve drops as the field is reduced from the saturated state. The spin wave modes in the ferromagnet should be easily observed by Brillouin Light Scattering. The spin waves in the antiferromagnet also show dramatic changes as the antiferromagnet structure is changed.