Frequency domain analysis of thin film head response

The behavior of a thin film head is analyzed by transforming the time dependen equations for domain wall motion and magnetization rotation into the frequency domain. The analysis presented shows that the slower domain wall motion restrains the faster process of magnetization rotation up to some critical frequency. Above this frequency, the response is determined mainly by the rotational process. The analysis also shows that the component of wall displacement or angular rotation in-phase with the applied field vanishes at some critical frequency, in agreement with reported experimental data.