Time transient measurement of magnetic head field by using electron beam tomography

The data rate of HDDs is increasing rapidly in accordance with the drastic growth in areal recording density. A detailed study of the switching characteristics of the write heads is therefore very important in order to enable us to develop high-frequency recording. The witching speed of the write field depends on the write current reversal time and the intrinsic head field reversal tune as indicated by Klassen[l],[2]. In their study, write field waveforms and their dependence on write current excitation were measured by an electron-beamtomography method, and the effect of eddy current loss of the pole, which is one of the critical issues in high-frequency recording, was examined.