Magneto-optical recording medium
AssigneeMitsubishi Chemical Corporation
InventorsTakumi Shimamori, Yoko Ikeda, Yoshinori Seki, Takeshi Kuriwada
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Abstract
A magneto-optical recording medium having, in the following order, a substrate, a magneto-optical recording layer having a Curie temperature of not less than 220.degree. C., and a reflective layer mainly composed of Ag and having a refractive index of not more than 0.5 at a wavelength of less than 600 nm is written with an external magnetic field and a laser beam with a wavelength of less than 600 nm while read-out is with the laser beam also at a wavelength less than 600 nm.
Claims9
A magneto-optical recording medium having a figure of merit, which is the product of the square root of a reflectivity and an actual magnetic Kerr rotation angle, of not less than 3.8 at a wavelength of less than 600 nm and a magnetic Kerr rotation angle of not less than 1.2 degree at a wavelength of less than 600 nm, said magneto-optical recording medium comprising:
- a substrate,
- a magneto-optical recording layer of 10 to 30 nm thick comprising a Tb--Fe--Co amorphous alloy in which the Co content is 15 to 60 atom % based on the total amount of the Co content and Fe content or a Nd--Tb--Fe--Co amorphous alloy in which the Co content is 20 to 60 atom % based on the total amount of the Co content and Fe content, and having a Curie temperature of not less than 220.degree. C.;
- and
- a reflective layer of 30 to 100 nm thick containing not less than 70 atom % Ag and having a refractive index of not more than 0.5 at a wavelength of less than 600 nm,
- the reflective layer being disposed on the magneto-optical recording layer which is disposed on the substrate.
Dependencies are inferred from the claim text.