Magneto-optical recording medium by magnetic field modulation with the use of smaller magnetic fields

A magneto-optical storage medium, including at least a storage layer, a non-magnetic layer, and a storage supplementary layer, the layers being formed in an arrangement in which a storage layer, a non-magnetic layer, and a storage supplementary layer are provided on a substrate in the stated order,

• wherein the storage supplementary layer is made of a ferrimagnetic material having a compensation temperature near room temperature and exhibiting an increased saturation magnetisation near a Curie point of the storage layer, and has a magnetisation that changes an orientation thereof at a portion of the storage supplementary layer according to a modulated external magnetic field, the portion having been heated in a storing operation.

A magneto-optical storage medium, including at least a storage layer, a non-magnetic layer, a storage supplementary layer, another non-magnetic layer, and a ferromagnetic material layer, the layers being formed in an arrangement in which a storage layer, a non-magnetic layer, a storage supplementary layer, a non-magnetic layer, and a ferroelectric layer are provided on a substrate in the stated order,

• wherein the storage supplementary layer is made of a ferrimagnetic material having a compensation temperature near room temperature and exhibiting an increased saturation magnetisation near a Curie point of the storage layer, and has a magnetisation that changes an orientation thereof at a portion of the storage supplementary layer according to a modulated external magnetic field, the portion having been heated in a storing operation.

A magneto-optical storage medium, including at least a storage layer, a non-magnetic layer, and a storage supplementary layer, the layers being formed in an arrangement in which a storage supplementary layer, a non-magnetic layer, and a storage layer are provided on a substrate in the stated order,

• wherein the storage supplementary layer is made of a ferrimagnetic material having a compensation temperature near room temperature and exhibiting an increased saturation magnetisation near a Curie point of the storage layer, and has a magnetisation that changes an orientation thereof at a portion of the storage supplementary layer according to a modulated external magnetic field, the portion having been heated in a storing operation.

A magneto-optical storage medium, including at least a storage layer, a non-magnetic layer, a storage supplementary layer, another non-magnetic layer, and a ferromagnetic material layer, the layers being formed in an arrangement in which a ferroelectric layer, a non-magnetic layer, a storage supplementary layer, a non-magnetic layer, and a storage layer are provided on a substrate in the stated order,

• wherein the storage supplementary layer is made of a ferrimagnetic material having a compensation temperature near room temperature and exhibiting an increased saturation magnetisation near a Curie point of the storage layer, and has a magnetisation that changes an orientation thereof at a portion of the storage supplementary layer according to a modulated external magnetic field, the portion having been heated in a storing operation.

A magneto-optical storage device for storing information with respect to a magneto-optical storage medium having a storage layer that has a coercive force that lowers with a temperature rise, a storage supplementary layer that is made of a ferrimagnetic material having a compensation temperature in the vicinity of room temperature and having saturation magnetization that increases in the vicinity of a Curie temperature of said storage layer, and a first non-magnetic layer provided between said storage layer and said storage supplementary layer, said magneto-optical storage device comprising:

• an optical head for projecting a light beam to said magneto-optical storage medium;
• and
• a magnetic head for, upon a storing operation, applying a modulated magnetic field so as to change a direction of a magnetization at a portion having been heated by said light beam.