High-Areal Density Recording Simulation of Three-Layered ECC Bit-Patterned Media With a Shielded Planar Head

2014 ◽  
Vol 50 (11) ◽  
pp. 1-4 ◽  
Author(s):  
Naoki Honda ◽  
Kiyoshi Yamakawa
Keyword(s):  
Areal Density ◽  
Bit Patterned Media ◽  
Patterned Media

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

Micromachines ◽  
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.

Impact of Touchdown Detection on Bit Patterned Media Robustness

2013 ◽  
Author(s):  
Jia-Yang Juang ◽  
Kuan-Te Lin
Keyword(s):  
Areal Density ◽  
Flying Height ◽  
Head Disk Interface ◽  
Bit Patterned Media ◽  
Patterned Media ◽  
Disk Interface ◽  
Recording Process ◽  
Friction Temperature ◽  
The Media ◽  
The Impact

Bit patterned media (BPM) is considered as a revolutionary technology to enable further increase of areal density of magnetic recording beyond 1 Tbits/in2 [1]. Implementing BPM technology, however, significantly increases the complexity of the recording process, but also poses tremendous tribological challenges on the head-disk interface (HDI) [2]. One of the major challenges facing BPM is touchdown detection by thermal flying-height control (TFC), in which a minute heater located near the read/write transducers is used to thermally protrude a small portion of the slider into contact with the disk, and the contact is then detected by directly or indirectly measuring the friction, temperature rise or vibration caused by the contact [3]–[7]. Most recording heads rely on touchdown detection to achieve a desired flying height (FH), which approaches sub-1-nm regime for many of today’s commercial drives. As a result sensitive and accurate touchdown detection is of critical importance for a reliable head-disk interface by reducing contact duration and unnecessary interaction between the slider and the disk. However, the impact of touchdown on the mechanical robustness of the media has not been properly studied.

Trellis-Based Detecting the Insertion and Deletion Bits for Bit-Patterned Media Recording

2014 ◽  
Vol 979 ◽  
pp. 54-57 ◽  
Author(s):  
Santi Koonkarnkhai ◽  
Piya Kovintavewat ◽  
Phongsak Keeratiwintakorn
Keyword(s):  
Detection Method ◽  
Signal To Noise Ratio ◽  
Areal Density ◽  
Specific Marker ◽  
Magnetic Medium ◽  
Bit Patterned Media ◽  
Patterned Media ◽  
Media Noise ◽  
Insertion And Deletion ◽  
Better Than

Bit-patterned media recording (BPMR) is one of the promising technologies for realizing an areal density up to 4 Tb/in2; however, it poses new challenges to read channel design, including the two-dimensional (2D) interference, media noise, and track mis-registration. Furthermore, the BPMR system encounters the insertion, deletion and substitution errors, which are primarily caused by mis-synchronization between the write clock and the island positions. In this paper, we propose a novel detection method that exploits the trellis structure to detect the occurrence of insertion/deletion bits. Specifically, the specific marker bits are inserted periodically inside an input data sequence before recording onto a magnetic medium. Hence, the branch metric calculation is monitored during the marker bits to determine if there is any insertion/deletion error in the system. Numerical results indicate that the proposed method can performs better than the conventional one in terms of the percentage of detection and the percentage of missed detection and false-alarm, especially at low signal-to-noise ratio scenario.

scholarly journals Directed Self-Assembly of Block Copolymer for Bit Patterned Media with Areal Density of 1.5 Teradot/Inch2 and Beyond

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
XiaoMin Yang ◽  
Shuaigang Xiao ◽  
Yautzong Hsu ◽  
Michael Feldbaum ◽  
Kim Lee ◽  
...  
Keyword(s):  
Block Copolymer ◽  
Self Assembly ◽  
Areal Density ◽  
Bit Patterned Media ◽  
Patterned Media

scholarly journals Modulation Code for Reducing Intertrack Interference on Staggered Bit-Patterned Media Recording

2020 ◽  
Vol 10 (15) ◽  
pp. 5295 ◽  
Author(s):  
Seongkwon Jeong ◽  
Jaejin Lee
Keyword(s):  
Storage System ◽  
Areal Density ◽  
Magnetic Storage ◽  
Two Dimensional ◽  
Bit Patterned Media ◽  
Patterned Media ◽  
Cross Track ◽  
Modulation Code ◽  
Intertrack Interference

A bit-patterned media recording (BPMR) system is a type of ultrahigh-capacity magnetic storage system that can extend to an areal density of 1 terabit per square inch or higher. However, because the space between islands in the down- and cross-track directions is reduced to extend the areal density, the effect of two-dimensional interference is increased. However, using a staggered array, which is one of the possible island distributions for BPMR, helps to decrease intertrack interference. A 7/10 modulation code for a staggered BPMR is proposed to avoid the effect of two-dimensional interference and provide distance among nonidentical codewords for improving the correcting capability.

Sign in / Sign up

Export Citation Format

Share Document