Micromagnetic Simulation Of Magnetic Process For Co-rare Earth Recording Thin Films

Hybrid recording is a novel kind of super-high density information storage method that can break through the super-paramagnetic limit and further increase the recording density as well as the writing and reading data rates of hard disk drives (HDD). It takes advantages from MO and magnetic recording methods. The message writing is by laser-assisted thermal magnetic recording and message reading is by magnetic flux detection with high sensitive GMR sensors. The studies on the developing of new hybrid recording media are very important to the increasing of the area density of HDD and to the implementation of hybrid recoding method. Therefore, this dissertation presents a theoretical and experimental investigation of micro-structure and physical properties as well as relative mechanism of SmDyCo, SmTbCo series thin films for hybrid recording.By using micro-magnetic model and micro-magnetic simulated software-SimulMag, we simulated the magnetic properties and dynamic magnetic process of SmDyCo single magnetic films and SmDyCo magnetic films with soft underlayer systemically. The simulation results were in good accord with the experimental results. The switching behaviors of exchange coupled layers under magnetic fields have been explained by using micro-magnetic model. Finally, we simulated the magnetic properties and readout properties of the exchange coupled double layers with a soft underlayer.By using micro-magnetic model and micro-magnetic simulated software-OOMMF, we simulated the hysteresis properties and magnetization process of SmTbCo single magnetic films systemically at different angles. By using micro-magnetic model, we studied hysteresis properties and the forming condition of the interface magnetic domains of SmTbCo exchange coupled layers. We explained the magnetization of SmTbCo exchange coupled layers. Finally, we studied the effect of film thickness for exchange energy density.