| Hybrid recording is a novel kind of super-high density data storage technology that can break through the super-paramagnetic limit, and further increase the area density as well as the writing and reading rates of hard disk drives (HDD). It takes advantages from Magneto-Optical (MO) and magnetic recording methods. The data writing is by laser-assisted thermal magnetic recording and the data reading is by magnetic flux detection with high sensitive GMR sensors. The studies on the developing of new media are very important to the increasing of the area density of HDD and to the implementation of hybrid recoding technology. Therefore, focusing on the target of researching and developing the new kind of hybrid recording media, this dissertation presents a theoretical and experimental investigation of micro- structure and physical properties as well as relative mechanism of SmTbCo series thin films.Theoretically, in order to solve the problems of the hybrid recording media need high anisotropy to ensure adequate thermo stability, the origins of TM-RE amorphous films possessing perpendicular anisotropy have been studied with the single ion model and magnetic dipolar model. The calculated results show that the dipolar interactions between the TM atoms and the RE atoms of the TM-RE amorphous film composing the minor part of the perpendicular anisotropy. The Coulomb interactions between the 4f electrons of the RE ion with the deformed local crystalline field, which produced in film sputtering deposition process, build up the high perpendicular anisotropy of RE-TM amorphous films. The interactions between the non-S state Tb ion in non-spherical electric charge distribution with the deformed local crystalline field accounts for the major source of high perpendicular anisotropy of TbCo amorphous films. On the other hand, in order to solve the problems of the hybrid recording media need high saturation magnetization to increase the signal noise ratio, the exchange coupled interactions between the TM atoms and RE atoms in the amorphous TM- RE films have also been studied. By making use of the characteristics of the ferri-magnetic structure and the difference of the exchange interaction between the LRE and HRE atoms with TM atoms in TM-RE amorphous films, through substituting the HRE atoms Tb with LRE atoms Sm, the SmTbCo/Cr amorphous films with perpendicular anisotropy and with excellent magnetic properties have been obtained. The temperature dependence curves of SmTbCo/Cr amorphous films have also been calculated with mean-field theory. The results are in good accord with experimental datum. Based on these, the effects of the single ion anisotropy on the calculation results with mean field theory have been investigated. The results show that there is little influence on the Curie temperature but there is obvious influence on the compensation temperature of the SmTbCo films by single ion magnetic anisotropy. The temperature dependence of the exchange interaction enhancing coefficients Ax in different composition of SmTbCo/Cr amorphous films has also been calculated. The results indicate that Ax is decreased with temperature increasing and it will be closed to zero when temperature reaches Curie point. The micro-magnetic model has been proposed according with the minimum energy principle. The forming conditions of the interface magnetic domains and the switching behaviors of TM-RE exchange coupled dual layers under external magnetic fields have been studied and the magnetization behaviors of the SmTbCo exchange coupled dual layer films have been reasonably explained. The exchange coupled status between the SmTbCo dual layer have also been studied through the calculation of the interface wall energy. Experimentally, in order to increase the coercivity of the hybrid recording media for increasing the area density, the influences of the magnetron sputtering parameters on the magnetic properties of TbCo films have been investigated. The optimal conditions to produce much high coercivity of TbCo films have been obtaine...
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