Spin Dynamics of Magnetic Disks in the Vortex State

Author

Zhu, Xiaobin ; Liu, Zhigang ; Metlushko, Vitali ; Freeman, Mark R.

Author_Institution

Seagate Res. Center, Pittsburgh

fYear

2007

fDate

17-21 Sept. 2007

Firstpage

613

Lastpage

616

Abstract

Spin dynamics of magnetic disks in the vortex state is studied by ultrafast optics. In patterned Co disks, we found that time-domain spin dynamics are strongly dictated by the transient field direction. For transient field directions applied parallel to the disk plane, an azimuthal spin-wave mode splitting of Co disks of greater than 2 GHz arises on account of the presence of the vortex core. In the NiFe/Cu/Co disks, even though the laser beam only probes the top NiFe disks, we observe that there exists a dominant high frequency resonance close to that of Co disks. This is due to the dynamic dipolar interaction between the Co and NiFe layers. Spin dynamics in a large array of NiFe disks also has been studied through examination of the time-resolved magneto-optical Kerr effect at diffraction spots.

Keywords

Kerr magneto-optical effect; cobalt; copper; ferromagnetic resonance; magnetic disc storage; nickel alloys; spin dynamics; vortices; Co; Co disks; Cu; Cu disks; NiFe; NiFe disks; azimuthal spin-wave mode splitting; dynamic dipolar interaction; high frequency resonance; laser beam; magnetic disks; time-domain spin dynamics; time-resolved magneto-optical Kerr effect; transient field direction; ultrafast optics; vortex state; Diffraction; Kerr effect; Laser beams; Laser modes; Magnetooptic effects; Probes; Resonance; Resonant frequency; Time domain analysis; Ultrafast optics;

fLanguage

English

Publisher

ieee

Conference_Titel

Electromagnetics in Advanced Applications, 2007. ICEAA 2007. International Conference on

Conference_Location

Torino

Print_ISBN

978-1-4244-0767-5

Electronic_ISBN

978-1-4244-0767-5

Type

conf

DOI

10.1109/ICEAA.2007.4387376

Filename

4387376