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Switching field distribution and magnetic behavior of patterned recording media


V.G. Shadrov – Ph.D. (Phys.-Math.), Leading Research Scientist, Scientific-Practical Materials Research Centre (Belarus) L.V. Nemtsevich – Research Scientist, Scientific-Practical Materials Research Centre (Belarus) A.V. Boltushkin – Ph.D. (Phys.-Math.), Senior Research Scientist, Scientific-Practical Materials Research Centre (Belarus). E-mail:

Magnetic behavior of patterned magnetic media and its dependence on intergranular magnetic interaction and switching field distribution, as well as its correlation with preparation conditions and exploitation characteristics are discussed on the basis of the domain structure investigations, irreversible susceptibility measurements and angular dependences of hysteresis characteristics. It is shown, that a key issue for exploiting patterned recording media is improving both thermal stability and writability, as well as switching field distribution (SFD) decreasing, which determines recording density and characterizes magnetic recording media quality. The SFD is determined by magnetic properties of the elements (particles) and the media (array) geometry. A significant influence on magnetization reversal processes and the SFD value renders a magnetostatic interaction between elements, increasing, in particular, the total SFD in magnetic media with perpendicular magnetic anisotropy. For reducing the intrinsic SFD in patterned media it is necessary to avoid defects or to create identical defects in each magnetic element. Another option may be exchange coupled composite patterned structures, where the element reversal is initiated by a nucleation assist layer. Graded media, in which the magnetic anisotropy gradually changes, and core-shell structures are proposed to further improve relation between writability and thermal stability.


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