Title :
Sub-nanosecond non-Arrhenius magnetic switching in perpendicular multilayers
Author :
Ju, Ganping ; van de Veerdonk, R.J.M. ; Svedberg, E.B. ; Wierman, K.W. ; Weller, D. ; Howard, K.J. ; Kryder, M.H. ; Tamaru, S. ; Wolfson, J.T. ; Bain, J.A.
Author_Institution :
Seagate Res., Pittsburgh, PA, USA
fDate :
7/1/2001 12:00:00 AM
Abstract :
Measurements are presented of sub-nanosecond magnetization reversal processes of perpendicularly magnetized (CoCr/Pt) multilayers using real-time Kerr microscopy. The multilayers are placed on a ring-type recording head which is used as a sub-ns risetime field source. In the gap of the write head the magnetic field direction changes rapidly from in-plane to out-of-plane. By scanning the laser beam across the gap the influence of the field angle on the reversal process is studied. The reversal time depends critically on the field angle, and faster switching occurs close to the gap (pole edge) due to the increase of the in-plane field. On the time scale of the study, the rotational (non-Arrhenius) switching seems to dominate
Keywords :
chromium alloys; cobalt alloys; ferromagnetic materials; magnetic heads; magnetic multilayers; magnetic switching; magnetisation reversal; perpendicular magnetic recording; platinum; CoCr-Pt; field angle; in-plane; magnetic field direction; magnetization reversal processes; out-of-plane; perpendicular multilayers; pole edge; real-time Kerr microscopy; reversal time; ring-type recording head; sub-nanosecond nonArrhenius magnetic switching; sub-ns risetime field source; time scale; write head; Delay; Magnetic fields; Magnetic heads; Magnetic multilayers; Magnetic recording; Magnetic switching; Magnetization reversal; Optical pulses; Perpendicular magnetic recording; Space vector pulse width modulation;
Journal_Title :
Magnetics, IEEE Transactions on
