| 摘要 |
PROBLEM TO BE SOLVED: To make information recordable with applying of a small alternating magnetic field on a magnetic layer having a large coercive force by allowing coercive forces, magnitudes of magnetization, film thicknesses, magnetization directions of a first magnetic layer in which information are recorded and held and a second magnetic layer and a boundary magnetic wall energy to respectively satisfy specific relations. SOLUTION: A recording and reproducing layer 13 whose coercive force, magnitude of magnetization and film thickness are respectively Hc1, Ms1 and t1 and a control layer 12 whose coercive force, magnitude of magnetization and film thickness are respectively Hc2, Ms2 and t2 are provided on the substrate 11 of a magnetic disk 1. A magnetic field in which magnetization directions of the recording and reproducing layer 13 and the control layer 12 become the same direction and a magnetic field in which only the recording and reproducing layer 13 is inverted are respectively made Hda, Hab and a magnetic field in which both magnetization directions of the layers 13, 12 become the same direction after the magnetic field Hab is applied on the layers is made Hba. Moreover, when the boundary the magnetic wall energy is madeσ, this magnetic recording medium has a magnetic characteristic satisfying Hab=Hc2-σ/2Ms1.2t2, Hab=-Hc1-σ/2Ms1.t1, Hab=Hc1-σ/2Ms1.t1. Thus, the recording of information is performed with the impressing of the small alternating magnetic field by using the magnetic layer having the large coercive force for a high density recording.
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