350 rub
Journal Electromagnetic Waves and Electronic Systems №1-2 for 2020 г.
Article in number:
Magnetic media for perpendicular magnetic recording
DOI: 10.18127/j15604128-202001-2-07
UDC: 539.216.2
Keywords: Perpendicular magnetic recording superparamagnetic limit recording density granular media exchanged-coupled media segmented media patterned media
Authors:

V.G. Shadrov – Ph.D.(Phys.-Math.), Leading Research Scientist, 
Scientific-Practical Materials Research Centre of NAS of Belarus (Minsk)
E-mail: nemtsevich@ifttp.bas-net.by

A.E. Dmitrieva – Junior Research Scientist, 
Scientific-Practical Materials Research Centre of NAS of Belarus (Minsk)
E-mail: nemtsevich@ifttp.bas-net.by

A.V. Boltushkin – Ph.D.(Phys.-Math.), Leading Research Scientist, 
Scientific-Practical Materials Research Centre of NAS of Belarus (Minsk) E-mail: nemtsevich@ifttp.bas-net.by

Abstract:

The invention and development of perpendicular magnetic recording has facilitated a great increase in areal density. For a recent years, however, data density increasing slows down due to trade-off between signal-to-noise ratio, thermal stability, and writability. As a solution, energy assisted magnetic recording and bit-patterned media are proposed. In the present paper the basic perpendicular recording media concepts and high anisotropy magnetic materials are analyzed as well as alternative materials and magnetic recording technologies. A further increase in the density of bits in magnetic storage media is possible on the basis of a compromise between maintaining the necessary signal-to-noise ratio, thermal stability of magnetic elements (grains) and achievable fields of recording heads, which involves the use of energy-assisted recording technologies and bit-structured media
In particular, the technology of thermally assisted magnetic recording involves a decrease in the average thermostable grain size to 3...4 nm and an increase in surface density to 4...5 Tb/inch2 in ordered L10 media based on FePt alloys. The need to heat the magnetic medium during recording to a value of the order of the Curie temperature requires optimization of the thermal properties of the magnetic layer, the parameters of the magnetic heads and the tribological characteristics of the head-to-disk interface. In particular, the implementation of HAMR technology involves maintaining the distribution of the magnetic field TC within 2%.
The problems of HAMR technology and the significant increase in the cost of its implementation create certain prerequisites for the implementation of MAMR on the basis of the existing technology of perpendicular recording, segmented recording media and the possibility of integrating a spin-transfer nano-oscillator into a reader / writer. An analysis of the magnetic properties of the materials of the recording media and read-write heads makes it possible to consider it reasonable to increase the surface density based on energy-recorded recordings up to 5 Tb/inch2. To achieve a surface recording density of 10 Tb/inch2 or higher, a combination of HAMR or MAMR and bit-structured technologies, including the use of multi-level structures, is considered.

Pages: 54-68
For citation

Shadrov V.G., Dmitrieva A.E., Boltushkin A.V. Magnetic media for perpendicular magnetic recording. Electromagnetic waves and electronic systems. 2020. V. 25. № 1–2. P. 54−68. DOI: 10.18127/j15604128-202001-2-07 (in Russian).

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Date of receipt: 21 марта 2019 г.