Picosecond time-resolved magnetization dynamics of thin-film heads

The application of picosecond magneto-optic sampling techniques to studies of the magnetization dynamics of thin-film recording heads is described. Time-resolved magnetization measurements are performed using picosecond stroboscopic scanning Kerr microscopy. A Faraday probe is used to monitor the coil excitation current with the same optical setup, yielding a direct measure of the magnetic propagation delay through the head. This delay is found to have a marked spatial dependence across the face of the pole tips. As an aid to visualization of the spatial dependence, scanned images of the polar Kerr rotation at fixed time delays are acquired. (C) 1996 American Institute of Physics.