Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-29T09:17:20.370Z Has data issue: false hasContentIssue false

Amorphous Rare Earth-Transition Metal Alloys for Magneto-Optical Storage

Published online by Cambridge University Press:  10 February 2011

Richard J. Gambino*
Affiliation:
Department of Materials Science and Engineering State University of New York at Stony Brook Stony Brook, NY 11794-2275, [email protected]
Get access

Abstract

Amorphous alloys of the heavy rare earth elements with cobalt and iron have magnetic and optical properties that make them ideally suited for magneto-optical mass storage media. These materials are used in all commercial erasable (MO) optical disk systems and in optically assisted magnetic storage such as the recordable music minidisk. The important properties of these materials for this application are: 1/ ferrimagnetic exchange with a magnetic compensation point near room temperature, 2/ perpendicular easy axis anisotropy when prepared under suitable conditions as thin films, 3/low media noise as compared to polycrystalline films, 4/low processing temperatures compatible with polymer substrates and 5/thermally stable when cycled repeatedly to the Curie temperature. The magneto-optical Kerr effect that is used to read the information off the disk is large at the 800 nm wavelength used in current devices but low at 400 nm. Since the areal storage density is set by the diffraction limit, improvements in shorter wavelength device performance are needed.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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

[1] Chaudhari, P., Cuomo, J. J. and Gambino, R. J., “Amorphous Metallic Films for Beam Addressable Applications,” Applied Phys. Lett. 22, 337 (1973). P. Chaudhari, J. J. Cuomo and R. J. Gambino, “Amorphous Metallic Films for Bubble Domain Applications,” IBM Journ. of Res. and Devel. 17, 66 (1973).10.1063/1.1654662Google Scholar
[2] Gambino, R. J. and Fumagalli, P., “Magneto-Optic Properties of Macroscopic Ferrimagnets,” IEEE Trans. Mag. 30, 4461 (1994)10.1109/20.334121Google Scholar
[3] Coey, J. M. D. and Readman, P. W., Nature, 246, 476 (1973);10.1038/246476a0Google Scholar
Moorjani, K. and Coey, J. D., Magnetic Glasses. Elsevier, Amsterdam, 1984 Google Scholar
[4] Pickart, S. J., Rhyne, J. J. and Alperin, H. A., Phys. Rev. Lett. 33, 424 (1974)10.1103/PhysRevLett.33.424Google Scholar
[5] Hiroyoshi, H. and Fukamichi, K., J. Appl. Phys. 53, 2226 (1982)10.1063/1.330779Google Scholar
[6] Slater - Pauling Curves, see Bozorth, R. M., Ferromagnetism IEEE Press Classic Reissue, 1993 10.1109/9780470544624Google Scholar
[7] Gambino, R. J. and McGuire, T. R., “Magneto-Optic Properties of Nd-Fe-Co Amorphous Alloys,” J. Appl. Phys. 57, 3906 (1985).10.1063/1.334911Google Scholar
[8] Gambino, R. J. and McGuire, T. R., “Enhanced Magneto-Optic Properties of Light Rare Earth-Transition Metal Amorphous Alloys,” J. Mag. Magn. Mat. 54–57, 1365 (1986).10.1016/0304-8853(86)90859-0Google Scholar
[9] Reim, W., Gambino, R. J., Ruf, R. R. and Plaskett, T. S., “TbxNdy(FeCo)1-x-y Promising Materials for Magneto-Optical Storage?”, J. Appl. Phys. 61, 3349 (1987).10.1063/1.338766Google Scholar
[10] Gambino, R. J., Ruf, R. R. and Bojarczuk, N. A., “Macroscopic Ferrimagnets as Magneto-Optic Media”, J. Appl. Phys. (Abstract: only) 75, 6871 (1994) N. A. Bojarczuk, R. J. Gambino and R. R. Ruf, U.S. Patent 5612131: Composite magneto-optic memory and media.10.1063/1.356813Google Scholar
[11] Gambino, R. J., “EuO/Tb-Fe-Co Exchange Coupled Films,” J. Magn. Soc. Japan 19 (Supplement No. S1), 17 (1995).10.3379/jmsjmag.19.S1_17Google Scholar
[12] Gambino, R. J., Wang, J. and McGuire, T. R., “Magnetoresistance of Co-EuS Macroscopic Ferrimagnets”, IEEE Trans. Mag. 31, 3915 (1995)10.1109/20.489815Google Scholar
[13] Chikazumi, S., Physics of Magnetism John Wiley, New York, 1964 Google Scholar
[14] Cargill, G. S. III, Gambino, R. J. and Cuomo, J. J., IEEE Trans. Mag. 10, 804 (1974)10.1109/TMAG.1974.1058397Google Scholar
[15] Cargill, G. S. III, and Cochrane, R. W. in Amorphous Magnetism, Hooper, H. O. and de Graaf, A. M., Editors, Plenum, New York, 1972, pp. 313320 Google Scholar
[16] Cargill, G. S. III and Mizoguchi, T., J. Appl. Phys. 49, 1753 (1978), J. Appl. Phys. 50, 3570 (1979)10.1063/1.324857Google Scholar
[17] Nèel, L., J. Phys. Radium, 15, 225 (1954)10.1051/jphysrad:01954001504022500Google Scholar
[18] Taniguchi, S., Sci. Rep. Res. Inst. Tohoku Univ. A7, 269 (1955)Google Scholar
[19] Mizoguchi, T., in Diffraction Studies on Non-Crystalline Substances, Hargittai, I. and Orville-Thomas, W. J., Elsevier, Amsterdam, 1981 Google Scholar
[20] Yan, X., Hirscher, M., Egami, T. and Marinero, E. E., Phys. Rev. B., 43, 9300 (1991)10.1103/PhysRevB.43.9300Google Scholar
[21] Harris, V. G., Aylesworth, K. D., Das, B. N.. Elam, W. T. and Koon, N. C., Phys. Rev. Letters, 69, 1939 (1992), V. G. Harris, K. D. Aylesworth, B. N. Das, W. T. Elam and N. C. Koon, IEEE Trans. Mag. 28, 2958 (1992)10.1103/PhysRevLett.69.1939Google Scholar
[22] Huffiagel, T. C., Brennan, S., Zschack, P., and Clemens, B. M., paper AD-02, Intermag Conf, Seattle, Washington, 1996 Google Scholar
[23] Rhyne, J. J., Pickart, S. J. and Alperin, H. A., Phys. Rev. Lett. 29, 1562 (1972)10.1103/PhysRevLett.29.1562Google Scholar
[24] Harris, R., Plischke, M. and Zuckermann, M. J., “New Model for Amorphous Magnetism”, Phys. Rev. Lett. 31, 160 (1973)10.1103/PhysRevLett.31.160Google Scholar
[25] Hasegawa, R., Gambino, R. J., Cuomo, J. J. and Ziegler, J. F., “Effect of Thermal Annealing and Ion Radiation on the Coercivity of Amorphous GdCo Films,” J. App. Phys. 45, 4036 (1974).10.1063/1.1663908Google Scholar
[26] Gambino, R. J., Ziegler, J. and Cuomo, J. J., “Effects of Ion Radiation Damage on the Magnetic Domain Structure of Amorphous Gd-Co Alloys,” Appl. Phys. Lett. 24, 99 (1974).10.1063/1.1655111Google Scholar
[27] Mizoguchi, T., Gambino, R. J., Hammer, W. N. and Cuomo, J. J., Effects of Ion Implantation Damage on the Magnetic Properties of Amorphous GdCoMo Films,” IEEE Trans. Magnetics, MAG–13, 1618, (1977).Google Scholar
[28] Katayama, T., Hasegawa, K., Kawanishi, K. and Tsushima, T., “Annealing Effects on Magnetic Properties of Amorphous GdCo, GdFe and GdCoMo Films”, J. Appi. Phys. 49, 1759 (1978)10.1063/1.324859Google Scholar
[29] Luborsky, F. E., “Kinetics for Changes in Anisotropy Coercivity and Argon Content of Transition Metal - Rare Earth Films”, J. Appl. Phys. 57, 3592 (1985)10.1063/1.335016Google Scholar