Thermally assisted magnetic recording with bit-patterned media to achieve areal recording density beyond 5Tb/in2

High-density bit-patterned media recording (BPMR) can be obtained by reducing the spacing between data bitislands in both the along-and across-track directions, thus leading to severe intersymbol interference (ISI) and intertrack interference (ITI) because of small bit and track pitches, respectively. Here, we propose to use the graph-based detector, instead of the trellis-based detector, in iterative decoding to combat the ISI and the ITI for a multi-head multi-track BPMR system. Specifically, the readback signal is sent to the graph-based detector before iteratively exchanging the soft information with a decoder. Experimental results indicate that at low to moderate complexity, the proposed scheme outperforms the existing schemes, especially at high recording density.

Download Full-text

Concatenated Coding Schemes for High Areal Density Bit-Patterned Media Magnetic Recording

IEEE Transactions on Magnetics ◽

10.1109/tmag.2017.2746339 ◽

2018 ◽

Vol 54 (2) ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Hidetoshi Saito

Keyword(s):

Magnetic Recording ◽

Areal Density ◽

Concatenated Coding ◽

Bit Patterned Media ◽

Patterned Media ◽

Coding Schemes

Download Full-text

Nanopatterned L10-FePt nanoparticles from single-source metallopolymer precursors for potential application in ferromagnetic bit-patterned media magnetic recording

Polymer Chemistry ◽

10.1039/c6py00714g ◽

2016 ◽

Vol 7 (27) ◽

pp. 4467-4475 ◽

Cited By ~ 27

Author(s):

Zhengong Meng ◽

Guijun Li ◽

Sheung-Mei Ng ◽

Hon-Fai Wong ◽

Sze-Chun Yiu ◽

...

Keyword(s):

High Throughput ◽

Magnetic Recording ◽

Potential Application ◽

Nanoimprint Lithography ◽

Fept Nanoparticles ◽

Single Source ◽

Bit Patterned Media ◽

Patterned Media

A new single-source metallopolymer precursor P was applied for the synthesis of magnetic FePt nanoparticles, which was also suitable for patterning by high-throughput nanoimprint lithography to obtain ferromagnetic nanolines.

Download Full-text

Micromagnetic Simulation of L10-FePt-Based Exchange-Coupled-Composite-Bit-Patterned Media with Microwave-Assisted Magnetic Recording at Ultrahigh Areal Density

Micromachines ◽

10.3390/mi12101264 ◽

2021 ◽

Vol 12 (10) ◽

pp. 1264

Author(s):

Pirat Khunkitti ◽

Naruemon Wannawong ◽

Chavakon Jongjaihan ◽

Apirat Siritaratiwat ◽

Anan Kruesubthaworn ◽

...

Keyword(s):

Magnetic Recording ◽

Magnetic Domain ◽

Hysteresis Loops ◽

Areal Density ◽

Bit Patterned Media ◽

Patterned Media ◽

Microwave Assisted ◽

The Media ◽

5 Ghz ◽

Exchange Coupled Composite

In this work, we propose exchange-coupled-composite-bit-patterned media (ECC-BPM) with microwave-assisted magnetic recording (MAMR) to improve the writability of the magnetic media at a 4 Tb/in2 recording density. The suitable values of the applied microwave field’s frequency and the exchange coupling between magnetic dots, Adot, of the proposed media were evaluated. It was found that the magnitude of the switching field, Hsw, of the bilayer ECC-BPM is significantly lower than that of a conventional BPM. Additionally, using the MAMR enables further reduction of Hsw of the ECC-BPM. The suitable frequency of the applied microwave field for the proposed media is 5 GHz. The dependence of Adot on the Hsw was additionally examined, showing that the Adot of 0.14 pJ/m is the most suitable value for the proposed bilayer ECC-BPM. The physical explanation of the Hsw of the media under a variation of MAMR and Adot was given. Hysteresis loops and the magnetic domain of the media were characterized to provide further details on the results. The lowest Hsw found in our proposed media is 12.2 kOe, achieved by the bilayer ECC-BPM with an Adot of 0.14 pJ/m using a 5 GHz MAMR.

Download Full-text