MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING APPARATUS
A magnetic recording medium for vertical magnetic recording includes a substrate, and a layer laminated on the substrate, including a first magnetic recording layer made of a granular material, an exchange-coupling-strength control layer, a second magnetic recording layer made of a granular material, and a third magnetic recording layer made of a non-granular material.
1 . A magnetic recording medium for vertical magnetic recording, comprising:
a substrate; and
a layer laminated on the substrate, including
a first magnetic recording layer made of a granular material,
an exchange-coupling-strength control layer,
a second magnetic recording layer made of a granular material, and
a third magnetic recording layer made of a non-granular material.
2 . The magnetic recording medium according to claim 1 , wherein
the first magnetic recording layer has an anisotropic magnetic field higher than an anisotropic magnetic field of the second magnetic recording layer.
3 . The magnetic recording medium according to claim 1 , wherein
the first magnetic recording layer has an anisotropic magnetic field lower than an anisotropic magnetic field of the second magnetic recording layer.
4 . The magnetic recording medium according to claim 1 , wherein
the first magnetic recording layer and the second magnetic recording layer are made of a granular material containing a CoCrPt alloy and an oxide, and
the third magnetic recording layer is made of an alloy material containing CoCrPt.
5 . The magnetic recording medium according to claim 1 , wherein
the exchange-coupling-strength control layer is made of Ru.
6 . A magnetic recording apparatus including a magnetic recording medium for vertical magnetic recording, the magnetic recording medium including
a substrate, and
a layer laminated on the substrate, including
a first magnetic recording layer made of a granular material,
an exchange-coupling-strength control layer,
a second magnetic recording layer made of a granular material, and
a third magnetic recording layer made of a non-granular material.
7 . The magnetic recording apparatus according to claim 6 , wherein
the first magnetic recording layer has an anisotropic magnetic field higher than an anisotropic magnetic field of the second magnetic recording layer.
8 . The magnetic recording apparatus according to claim 6 , wherein
the first magnetic recording layer has an anisotropic magnetic field lower than an anisotropic magnetic field of the second magnetic recording layer.
9 . The magnetic recording apparatus according to claim 6 , wherein
the first magnetic recording layer and the second magnetic recording layer are made of a granular material containing a CoCrPt alloy and an oxide, and
the third magnetic recording layer is made of an alloy material containing CoCrPt.
10 . The magnetic recording apparatus according to claim 6 , wherein
the exchange-coupling-strength control layer is made of Ru.