V.G. Shadrov - Ph.D. (Phys.-Math.), Leading Research Scientist, Scientific-Practical Materials Research Centre (Minsk) A.E. Dmitrieva - Junior Research Scientist, Scientific-Practical Materials Research Centre (Minsk) A.V. Boltushkin - Ph.D. (Phys.-Math.), Senior Research Scientist, Scientific-Practical Materials Research Centre (Minsk). E-mail: nemtsevich@ifttp.bas-net.by

The preservation of the growth rates density magnetic recording of the last two decades due to the advances in materials science magnetic media, among which is noted magnetoresistive read head, antiferromagnet-associated medium is a longitudinal magnetic recording medium granular oxide perpendicular magnetic recording, and servo systems and development of fundamental problems of physics of magnetism, among which the most important are the processes of magnetization reversal superparamagnetism of small particles and the thermal stability of magnetic recording media, the relationship of the processes of magnetization reversal with magnetic intergranular interaction and operational characteristics of magnetic nanostructures. Based on the research of magnetic time effects in the work of analyzes role of heat activated magnetization reversal processes in magnetic recording media, in particular their relation with the magnetic interaction between individual magnetic elements (particles), the distribution of the fields of magnetization reversal, thermal stability of magnetic media and magnetic recording density. It is shown, in particular, that the thermal stability of the multilayer structured environments increases with the number of layers, thus changing the mechanism of magnetization reversal can be reduced the magnitude of the coercive force HC and the width of the field distribution for magnetization reversal while maintaining the thermal stability. The distribution of values of the energy barriers for the studied high-packed structured environments and the average values of the HC is sufficiently large and is due to the dipole interaction. For further growth of the density of magnetic recording it is necessary to maintain a balance between signal-to-noise resistant small grains of the magnetic recording medium and opportunity (field records) head records (writability). In the framework of the traditional concept of magnetic recording media this involves the use of metabolic-related environments, particularly environments with a smooth change of the anisotropy and the structures of core-shell and termeszettudomanyi and microwave assisted magnetic recording, and more high anisotropic magnetic materials, primarily L10 FePt. The transition to a (bit)structured environments characterizes the change in the concept of magnetic recording, the maximum recording density involves a combination of technologies of creation of the structured environments with heat activated magnetic recording and accounting for thermal writаbility as another optimization parameter of the magnetic recording media.

 

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