Perpendicular magnetic recording

✍ Scribed by Sakhrat Khizroev, Dmitri Litvinov

• Publisher: Springer
• Year: 2004
• Tongue: English
• Leaves: 187
• Edition: 1
• Category: Library

✦ Synopsis

Magnetic recording is expected to become core technology in a multi-billion dollar industry in the in the very near future. Some of the most critical discoveries regarding perpendicular write and playback heads and perpendicular media were made only during the last several years as a result of extensive and intensive research in both academia and industry in their fierce race to extend the superparamagnetic limit in the magnetic recording media. These discoveries appear to be critical for implementing perpendicular magnetic recording into an actual disk drive. This book addresses all the open questions and issues which need to be resolved before perpendicular recording can finally be implemented successfully, and is the first monograph in many years to address this subject. This book is intended for graduate students, young engineers and even senior and more experienced researchers in this field who need to acquire adequate knowledge of the physics of perpendicular magnetic recording in order to further develop the field of perpendicular recording.

✦ Table of Contents

Table of Contents......Page 6
Preface......Page 10
Acknowledgements......Page 11
1. A Historical Perspective......Page 14
2. Superparamagnetic Limit......Page 15
3.1 Strong write field......Page 18
3.2 Perfectly aligned media......Page 22
3.3 Absence of the demagnetization field in bit transitions......Page 23
4. Soft underlayer as a new system component......Page 24
4.1 SUL as a major source of noise......Page 25
4.2 SUL magnetic moment......Page 26
4.3 SUL thickness......Page 27
4.4 SUL influence on the resolution......Page 28
5. Playback: New Signal Processing Schemes......Page 29
6. Challenges of New Materials......Page 30
6.1 Hard layer materials......Page 31
7. How Far Will Perpendicular Recording Go?......Page 34
1. Introduction......Page 36
2. Different Modes of Perpendicular Recording......Page 37
2.1 Second perpendicular mode: a ring head and a perpendicular medium without a soft underlayer......Page 38
2.2 First perpendicular mode: a single pole head and a perpendicular medium with a soft underlayer......Page 44
2.3 Modified first perpendicular mode: a shielded single pole head and a perpendicular medium with a soft underlayer......Page 92
1.1 Chapter overview......Page 98
2.1 Analysis Methods......Page 99
1.1 Chapter overview......Page 140
2.1 Types of Media......Page 141
2.3 Magnetic Field Calculation......Page 144
2.4 Demagnetisation Field in Perpendicular Recording Layer......Page 148
2.5 Stray Field from Perpendicular Magnetic Media......Page 150
2.6 Well-defined Perpendicular Easy Axis: Thicker Recording Layer?......Page 155
3. Soft Underlayer......Page 157
3.1 Saturation Moment......Page 158
3.2 Thickness of Soft Underlayer......Page 159
3.3 SUL-to-ABS Separation......Page 162
3.4 Anisotropy: Micromagnetics of SUL......Page 163
3.5 Magnetic Biasing......Page 166
3.6 Dynamics of Perpendicular Recording......Page 168
References......Page 175
N......Page 186
X......Page 187