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Magnetization Dynamics Investigated by Time-Resolved Kerr Effect Magnetometry

  • Jürgen Fassbender
Chapter
Part of the Topics in Applied Physics book series (TAP, volume 87)

Abstract

This review is divided into two main parts. In the first part, the magnetization dynamics of thin films and particles are addressed by numerical simulations. The coherent magnetization reversal behavior of homogeneously magnetized entities is addressed within the frame of the Stoner model. The trajectory of magnetization upon application of a magnetic field pulse is determined by the effective field, the magnetic damping parameter, and the magnetic field-pulse parameters. An appropriate choice of each of these parameters allow tailoring the magnetization precession, which in turn can be used to increase the performance of potential devices.

In the second part, after a brief description of the time-resolved magneto-optic Kerr effect magnetometer (TR-MOKE) setup, the experimental results of the magnetization dynamics of thin ferrite films are presented. First, the external control of magnetization dynamics is addressed in detail. It is shown that suppression of the magnetization precession after termination of the magnetic field pulse can be achieved in the entire sample. Then, the propagation of spin-wave packets is visualized and analyzed. Thereafter, the magneto-optic response of precessing magnetization is calculated and compared to experimental results. The perfect agreement observed further supports the assumption of a homogeneous magnetization distribution and thus the applicability of the Stoner model described in the first part of the review.

Keywords

Magnetization Reversal Magnetization Direction Shape Anisotropy Uniaxial Anisotropy Magnetization Dynamic 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Jürgen Fassbender
    • 1
  1. 1.Fachbereich PhysikUniversität KaiserslauternKaiserslauternGermany

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