The Barkhausen effect in single crystals

A new description of a single Barkhausen event is proposed. A reinterpretation of the small amplitude domain wall motion equation of Kittel and Galt is used. The model assumes that the Barkhausen Effect originates from the interaction of a moving domain wall with a parabolic potential well which is due to a distribution of defects. Single crystals of 3% Si-Fe served as the test material. Experiments showed that the average pulse half-height width varied linearly with sample thickness for small rectangular samples. Experiments with window frame samples at room temperature and at liquid nitrogen temperature showed that as the temperature was lowered the pulse half-height width increased and the number of pulses observed decreased. The origin of the negative Barkhausen Effect previously reported is explained in terms of pulse shape distortion due to bandwidth limitations.