Chaotic oscillation of domain wall in non-equilibrium state

The nonlinear equation of the Bloch wall motion is presented by modifying the Slonczewski equation based on the Landau-Lifshitz-Gilbert equation. The nonlinear force of restitution caused by an internal stress and an eddy current damping are added. Computer simulation is performed using the fourth Runge-Kutta method. The amplitude of the domain wall oscillation in the frequency region from 50 kHz to 1 MHz is calculated and compared with the experimental values for a CoZrMo/SiO/sub 2/ multilayered core. The experimentally observed decrease of amplitude with increasing frequency is reproduced well. Using computer simulation the chaotic oscillation of a domain wall in an ideal potential well is shown to appear in spite of no randomness. Another chaotic oscillation of the domain wall with Barkhausen jumps from one potential to the neighbor is shown.<
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