Patterned Magnetic Recording Media

Abstract

▪ Abstract Continuing increases in the areal density of hard disk drives will be limited by thermal instability of the thin film medium. Patterned media, in which data are stored in an array of single-domain magnetic particles, have been suggested as a means to overcome this limitation and to enable recording densities of up to 150 Gbit cm−2 (1 Tbit inch−2) to be achieved. However, the implementation of patterned media requires fabrication of sub-50-nm features over large areas and the design of recording systems that differ substantially from those used in conventional hard drives. This review describes patterned media, including the fabrication of arrays of small magnetic particles and their magnetic properties, such as domain structure, reversal mechanisms, thermal stability, and interactions. The practical implementation of patterned media recording schemes is assessed.

A micromagnetic study of the reversal mechanism in permalloy antidot arrays

“…The structures are characterized by a square lattice and, if not differently specified, contain square holes with variable size h. The spatial period p (i.e., the dimension of the square unit cell) is kept constant at 200 nm in all simulations. The samples are discretized using a 2D grid containing finite difference cells of size 3.125 Â 3.125 Â 20 nm 3 , providing a resolution in the xy-plane lower than the exchange length. The simulations are performed using the software package MUMAX, 44 which runs on Graphics Processing Units (GPUs), providing a computational speedup of up to two orders of magnitude compared to standard CPUs.…”

“…[1][2][3] Specific attention has been devoted to recording processes, studying the magnetic domain configuration at the remanent state to obtain small isolated regions where the basic unit of information could be stored. [4][5][6][7][8] Magnetotransport and hysteresis properties have been investigated in detail, considering different materials and analyzing the role of lattice configuration, hole shape, and geometrical parameters, such as the hole size and the interhole distance.…”

Hybrid metal–polymer composites from functional block copolymers

“…Discrete nanometerscale magnetic regions, such as those found in materials containing magnetic metallic nanoparticles, appear to be one promising choice in information storage, for which magnetic and optical storage components as small as tens of nanometers might be needed in the future. 45,46 Synthetic Strategies toward Metal-Containing Block Copolymers…”

The dynamical response to the node defect in thermally activated remagnetization of magnetic dot array

“…The technology of fabrication of MDAs [10,11,12,13] has been perfected to an excellent degree in the past few years. In practice, however, an occurrence of technological defects and local irregularities has still a great influence on all of the magnetic properties [14].…”