| Nowadays is information age, magnetic store has been the most capital instrument in the storage of messages. As the deal of digital information which people attend to steps up constantly, people bring up higher request about storage capacity and performance continuously. That how to increase the magnetic store domain density and abridge the response time of read/write is the problem that schoolers who work at magnetic material have to resolve all the time.As a memory media, nanomagnetic thin film have expansive applicatives for high-density recording devices,MRAM and magnetic sensors. the circular element is an ideal candidate which can be packed closely for high density magnetic recording applications. However, for the circular elements, it is difficult to control the remanent state magnetic rotation directions, i.e., clockwise or counterclockwise directions, for information storage applications. The inductiveness of artificial defects in the circular element changed the magnetization reversal pattern and remanent states of magnetics, which is a improve for the circular geometry. While it make the reverse magnetization process to be controlled easily. In resont years, the study on the circular magnetics which contain figurate defects have been being the hot spots.Before these technologys become products, the micromagnetic study on patterned thin film media with artificial defects is very necessary, which not only make us profound grasp the magnetization reversal mechanisms, but also provide beneficial guidance how to improve the performance of magnetic recording. In this paper, remanent states and magnetization reversal for polycrystalline Co slotted-disks and slotted-rings have been investigated using OOMMF micromagnetic calculated shoftware, with different combinations of diameter,slotted angle(α),thickness and applied field directions. Our results as follows:(1) The 400-nm-diameter Co slotted disks were simulated. Different combinations of disk thickness and slot angles were studied using orthogonal applied field directions (perpendicular and parallel to the slot angle (α)). We found that: the shape anisotropy has great impact on magnetization reversal, while the applied field directions have effect on the magnetic hysteresis and remanent states: When the applied field was perpendicular to the slot direction, the remanent states of all the magnetic elements are Flux-closure configuration, the coercivity, remanent magnetism degrade with the accession in thinkness of disks, or the minishing of sector chip. For the parallel direction applied field, the remanent magnetization of slotted disks degrade with the increase of thinkness and sector chip of magnets, while the variety in coercivity are complicate.(2) The remanent state and magnetization revesal of 30-nm-thick Co slotted rings were simulated individually and in 2×2 arrays with different interelement distances, the field was orthogonal directions too. We found that: the shape anisotropy and the directions of applied field have great effects on the remanent state of the slotted-rings, no matter how the rings arrange (individually or in 2×2 arrays). The distribution of magnetic moment and magnetic rotation directions of the remanent state were decide by the direction of applied field: When the field applied perpendicular to the slots, the remanent states of all the magnetic elements are Flux-closure configuration. The width of annular magnetic affects the remanent magnetization and coercivity too.In 2×2 arrays of slotted rings with the thinkness of 30nm [OD/ID (nm): 300/50, ], The interelement distance have effects on the shape of hysteresis, the distribution of magnetization vector in remanent state, coercivity and remanent magnetization due to the static coupling action of neighboring elements, When the distance is twice as outer diameter, it's affection could be ignored.α=60o...
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