Optical modulation overwritable magnetooptical recording medium
Abstract
Abstract A magnetooptical recording medium of this invention includes a transparent substrate, a first magnetic layer composed chiefly of GdFeCo and serving as a reproducing layer, a second magnetic layer serving as a memory layer, a third magnetic layer serving as an intermediate layer, a fourth magnetic layer serving as a writing layer, a fifth magnetic layer serving as a switching layer, and a sixth magnetic layer serving as an initializing layer. In this recording medium, the first, second, third, fourth, fifth and sixth magnetic layers are laid down over the substrate in this order, coercive-force energy of the fourth magnetic layer near a Curie temperature of the second magnetic layer is over 5×10 4 erg/cc, and a relation of 2E w t w <σ s -σ c is satisfied at room temperature where E w , t w , σ s and σ c are respectively coercive-force energy of the fourth magnetic layer, a layer thickness of the fourth magnetic layer, an energy density of an interfacial magnetic wall to be formed in the fifth magnetic layer and an energy density of an interfacial magnetic wall to be formed in the third magnetic layer.
Inventors
- 👤 Takashi Ikeda
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
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