Direct observation of the dynamic magnetic action in metal-in-gap recording heads

The behavior of the dynamic magnetic switching of metal-in-gap recording heads, observed directly through the use of the magnetooptic Kerr effect, shows significant magnetic action in the vicinity of poorly formed interfaces between Sendust and ferrite. A series of MnZn ferrite heads with increasingly better interfaces between the ferrite and Sendust is examined, and results from magnetooptic measurements are correlated with recording characteristics on media with coercivities of 900 Oe. No magnetic discontinuity at the interface of the best head is detectable by either technique, demonstrating that careful control of the interface can enhance the magnetic coupling between Sendust and ferrite to an acceptable level for suitable recording characteristics on such media