Articles you may be interested inMagnetization reversal and microstructure of FePt-Ag (001) particulate thin films for perpendicular magnetic recording media Improved coercivity was achieved in perpendicular 10-nm-thick FePt film through an inserted Ag layer. The out-of-plane coercivity increased with increasing Ag thickness, from 2.0 kOe, for the sample without Ag, to 4.4 kOe, for the sample with 3 nm Ag. Silver insertion also reduced the magnetic grain size and affected the magnetic reversal mode in these films.

The effect of thermal energy (kBT), which has been found to play some important roles in the magnetic properties of recently developed antiferromagnetically coupled media, is described. It was observed that the thermal energy helps to obtain an antiparallel configuration of moments at remanence. Therefore, a reduction in the remnant moment–thickness product (Mrδ) is observed, even for smaller values of J (interface coupling constant) than those used in simulations that do not consider thermal energy. The magnetic viscosity measurement helps to distinguish the magnetization decay behavior of the top and bottom layers. The magnetic moments of top and bottom layers show maximum decay at different fields and the decay rates approximately scale with their thickness. Viscosity results also point out that the magnetization reversal of the bottom layer should occur in the first quadrant, in order to obtain a low noise and thermally stable media. Micromagnetic simulation was performed by including thermal effects. In that case, Mrδ reduction could be obtained for smaller values of J than in the case where thermal energy is not included in the simulation.