Abstract: A method for manufacturing a magneto-optical recording medium in which reading of recorded information is performed through domain wall displacement in a reproduction layer is provided, in which magnetic separation of groove side-wall portions is performed more reliably; as a result a magneto-optical recording medium with satisfactory recording and reproduction characteristics can be provided.

Abstract: Provided is a magneto-optical recording medium capable of accurately reproducing a signal of a recording density exceeding a resolution of an optical system without making a constitution thereof complicated. The magnetic domain wall displacement type magneto-optical recording medium, comprises: a magnetic domain wall displacement layer in which a magnetic domain wall moves to contribute to information reproduction; a memory layer holding a recorded magnetic domain corresponding to the information; and a switching layer which is arranged between the magnetic domain wall displacement layer and the memory layer and has a Curie temperature lower than Curie temperatures of the magnetic domain wall displacement layer and the memory layer.

Abstract: A domain-wall-displacement-type magnetooptical recording medium is provided in which a floating magnetic field from a surrounding portion that operates on a recording/reproducing portion is suppressed. The recording medium includes a displacement layer having a composition such that rare-earth-element sub-lattice magnetization is dominant at room temperature, a switching layer, a memory layer, and a magnetization compensation layer in which iron-family-element sub-lattice magnetization is dominant at room temperature, for suppressing generation of a stray magnetic field at a temperature near room temperature.

Abstract: The present invention provides a method of recording information on a magneto-optical recording medium of domain wall displacement type having a preformat area and a data area succeeding thereto, comprising the steps of generating a reproduction signal from said medium by utilizing a light beam, detecting a reference position based on said reproduction signal, determining, based on a result of the detection, a recording start timing at which a formation of a recording magnetic domain is started at a distance at least not shorter than a displacement amount of a domain wall away from a start position of said data area; and starting a recording with said determined recording start timing.

Abstract: In reproduction from a magneto-optical recording medium by the domain wall displacement detection method, it is possible to avoid occurrence of ghost signals and to improve dropout, and moreover design of magnetic layers is made easy. A configuration is adopted having at least, in order from the side of incidence of laser light for reproduction, a first magnetic layer 11 constituting a reproduction layer, a second magnetic layer 12 constituting a control layer, a third magnetic layer 13 constituting a blocking layer, and a fourth magnetic layer 14 constituting a recording layer, which if the respective Curie temperatures thereof are TC1, TC2, TC3 and TC4, satisfy the relations TC1>TC3>TC2 and TC4>TC3. At the same time, if the magnetic anisotropy of the second magnetic layer is Ku2 and the magnetic anisotropy of the third magnetic layer is Ku3, the relation Ku3>Ku2 is satisfied.

Abstract: A magneto-optical medium of a domain wall displacement type is provided which does not cause inward leakage of signals caused by domain wall displacement from the rear of a reproducing light spot. The magneto-optical medium comprises a domain wall displacement layer, a switching layer, and a memory layer. The switching layer has a boundary temperature higher than room temperature for transformation from a state of a perpendicular magnetization film to a state of an in-plane magnetization film.

Abstract: A domain-wall-displacement-type magnetooptical recording medium is provided in which a floating magnetic field from a surrounding portion that operates on a recording/reproducing portion is suppressed. The recording medium includes a displacement layer having a composition such that rare-earth-element sub-lattice magnetization is dominant at room temperature, a switching layer, a memory layer, and a magnetization compensation layer in which iron-family-element sub-lattice magnetization is dominant at room temperature, for suppressing generation of a stray magnetic field at a temperature near room temperature.

Abstract: A manufacturing method of a domain wall displacement type magneto-optical recording medium comprises the steps of depositing a magnetic layer on a substrate to prepare a disc, and irradiating the magnetic layer with a converged light beam while applying a magnetic field and annealing the magnetic layer a converged light beam between information tracks.

Abstract: By irradiating a light beam between recording tracks of the magneto-optical recording medium, the magnetic anisotropy of at least one layer selected from the group consisting of the domain wall displacement layer and the recording layer formed between the recording tracks can be made lower than that of said layers on the recording tracks, and a bias magnetic field is applied at least between recording tracks while a light beam is radiated. Because of this, initialization of a medium may be conducted simultaneously.

Abstract: A signal reproducing method for reproducing information by domain wall displacement on a recording medium having recorded information comprises steps of projecting a light spot onto the recording medium to cause temperature distribution thereon, moving relatively the light spot and the recording medium, applying a reproducing magnetic field to the light spot area on the recording medium to prevent displacement of the domain wall from the rear portion of the moving light spot into the inside thereof, and detecting the domain wall displacement to reproduce the information. The temperature gradient may satisfy the relation below: |G1|>|G2| where G1 is the temperature gradient in the front portion in the moving direction, and G2 is the temperature gradient in the rear portion in the moving direction.