Noise factors in detection of minute marks by domain wall displacement

Author

Kaneko, Masahiko ; Yoshimura, Sunji ; Fujita, Goro ; Kobayashi, Seiji

Author_Institution

Sony Corp., Tokyo, Japan

Volume

36

Issue

5

fYear

2000

fDate

9/1/2000 12:00:00 AM

Firstpage

2266

Lastpage

2270

Abstract

Causes of data errors by DWDD and dominant noise factors which determine the density are discussed. Dropout of data mainly occurs during readout by domain wall displacement at mark length less than 110 nm. The bit shift causes serious data error when window width is shorter than 70 nm. A novel method has been introduced to analyze the jitter by reading the signal many times for the same area and by averaging the waveform. The space-dependent jitter obtained by averaging is 8.8 nm and is greater than the time-dependent jitter of 6.7 nm caused by the shot noise, the laser noise, and the system noise as well as caused by the fluctuation of the domain wall displacement. Comparison with the ordinary structured MO media has revealed that a bit length of 77 nm will be available when the space-dependent jitter is reduced to 3.8 nm which is the value for ordinary structured media

Keywords

jitter; laser noise; magnetic domain walls; magnetic recording noise; magneto-optical recording; shot noise; thermal stability; bit shift; data dropout; data errors; domain wall displacement; laser noise; minute marks detection; noise factors; shot noise; space-dependent jitter; structured magneto-optical media; system noise; thermal stability; wall displacement fluctuation; Coercive force; Jitter; Magnetic anisotropy; Magnetic domain walls; Magnetic domains; Magnetic materials; Magnetic separation; Magnetooptic recording; Perpendicular magnetic anisotropy; Perpendicular magnetic recording;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.908388

Filename

908388