Hostname: page-component-76fb5796d-skm99 Total loading time: 0 Render date: 2024-04-26T04:09:08.762Z Has data issue: false hasContentIssue false
  • English
  • Français

Overwritable Double-Layered Magneto-Optic Disk Media

Published online by Cambridge University Press:  21 February 2011

Osamu Ishii  and
Iwao Hatakeyama
Osamu Ishii
Affiliation:
NTT Applied Electronics Laboratories, Tokai-mura, Ibaraki-ken 319-11. Japan
Iwao Hatakeyama
Affiliation:
NTT Applied Electronics Laboratories, Tokai-mura, Ibaraki-ken 319-11. Japan
Get access

Abstract

An overwritable magneto-optic disk with a double-layered medium is described. The medium consists of magnetic recording (low coercivity, Hc, and high Curie temperature. Tc) and reproducing (high Hc and low Tc) layers. After a magnetic head writes data on a recording layer. a laser beam from an optical head irradiates a written track to heat a reproducing layer above its Tc. During cooling, the reproducing layer is magnetized by the flux from the bits on the recording layer with a width equal to that of the focused laser beam. These printed bits are read with the optical head. By repeating the above operations. the overwrite process is achieved. This overwrite mechanism is confirmed by using a Gd-Tb-Fe-Co (low Hc and high Tc)/ Tb-Fe (high Hc and low Tc) double-layered medium, a Winchester type magnetic head and an optical head. A wide gap magnetic head can write 1 μ m bits on the recording layer at a 0.52 μm flying height. Such wide spacing is promising for increased operational stability. Magnetic writing is of great advantage in increasing the recording density due to its rectangular bit shape.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 150: Symposium F – Materials for Magneto-Optic Data Storage , 1989 , 143
Copyright
Copyright © Materials Research Society 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Freese, R.P.. IEEE Spectrum. 25, 41 (1988).Google Scholar
2. Nakao, T., Ojima, M.. Miyamura, Y., Okamine, S. and Takeuchi, Y., J. J. Appl. Phys. supp. 26–4. 149 (1987).Google Scholar
3. Saito, J., Sato, M., Matsumoto, M. and Akasaka, M.. J. J. Appl. Phys. supp. 26–4, 155 (1987).Google Scholar
4. Shieh, H.D. and Kryder, I. H., Appl. Phys, Lett. 49, 473 (1986).Google Scholar
5. Rugar, D., IEEE Trans. Magn. MAG–24, 666 (1988).Google Scholar
6. Iwasaki, S. and Ouchi, K., IEEE Trans. Magn. MAG–14. 849 (1978).Google Scholar
7. Bernstein, P. and Gueugnon, C., J. Appl. Phys. 57, 3601 (1985).Google Scholar
8. Imamura, N., Tanaka, S., Tanaka, F. and Nagao, Y., IEEE Trans. Magn. MAG–21, 1607 (1985).Google Scholar
9. Iwasaki, S. and Nakamura, Y., IEEE Trans. Magn. MAG–13, 1272 (1977).Google Scholar
10. Mitsuya, Y. and Takanami, S., IEEE Trans. Magn. MAG–23, 2674 (1987).Google Scholar
11. Ohtani, Y., to be presented at the International Conference of Perpendicular Magnetic Recording, Tokyo, Japan, 1989 Google Scholar