Abstract: A patterned perpendicular magnetic recording disk has a pre-patterned disk substrate with pillars and trenches arranged in data regions and servo regions. In the data regions, the height of the data pillars is equal to or greater than the spacing between the data pillars, while in the servo regions the height of the servo pillars is less than the spacing between the servo pillars. A magnetic recording material with perpendicular magnetic anisotropy is deposited over the entire disk substrate, which results in magnetic material on the tops of the data pillars and servo pillars and in the servo trenches. The material in the data trenches is either nonmagnetic or discontinuous. After the application of a high DC magnetic field in one perpendicular direction and a low DC magnetic field in the opposite direction, the resulting disk has patterned servo sectors with servo pillars all magnetized in the same perpendicular direction and servo trenches magnetized in the opposite perpendicular direction.

Abstract: A patterned-media magnetic recording disk drive uses an optical system for accurately clocking the write data. The disk has concentric data tracks patterned into discrete magnetizable data islands with nonmagnetic spaces between the islands. As the disk rotates, a radiation source directs near-field radiation to the islands and spaces, and a radiation detector receives reflected radiation. The radiation is directed from the source through an optical channel or waveguide on the air-bearing slider that supports the read and write heads. The optical channel or waveguide has a near-field transducer at the disk-facing surface of the slider where the near-field radiation exits and reflected radiation returns. The reflected optical power varies depending on whether the near-field transducer couples to an island or a space, so the radiation detector output signal represents the frequency and phase of the islands as the disk rotates.

Abstract: A patterned perpendicular magnetic recording disk has a pre-patterned disk substrate with pillars and trenches arranged in data regions and servo regions. In the data regions, the height of the data pillars is equal to or greater than the spacing between the data pillars, while in the servo regions the height of the servo pillars is less than the spacing between the servo pillars. A magnetic recording material with perpendicular magnetic anisotropy is deposited over the entire disk substrate, which results in magnetic material on the tops of the data pillars and servo pillars and in the servo trenches. The material in the data trenches is either nonmagnetic or discontinuous. After the application of a high DC magnetic field in one perpendicular direction and a low DC magnetic field in the opposite direction, the resulting disk has patterned servo sectors with servo pillars all magnetized in the same perpendicular direction and servo trenches magnetized in the opposite perpendicular direction.

Abstract: A patterned-media magnetic recording disk drive uses an optical system for clocking the write data and a patterned-media disk that has discrete magnetizable data islands with nonmagnetic spaces between the islands, wherein the nonmagnetic spaces contain optical contrast material. The optical contrast material may be optically absorptive material, fluorescent material, or a metal layer that generates surface plasmons when excited by radiation of a specific wavelength. Radiation from a primary radiation source is directed to a near-field transducer maintained near the disk surface and a radiation detector detects radiation reflected back from the transducer. If the disk has fluorescent material or a metal layer in the nonmagnetic spaces, then a secondary radiation source irradiates the fluorescent material or metal layer with radiation of a specific wavelength to cause the fluorescent material to emit radiation or the metal layer to generate surface plasmons.

Abstract: A patterned-media magnetic recording disk drive uses an optical system for clocking the write data and a patterned-media disk that has discrete magnetizable data islands with nonmagnetic spaces between the islands, wherein the nonmagnetic spaces contain optical contrast material. The optical contrast material may be optically absorptive material, fluorescent material, or a metal layer that generates surface plasmons when excited by radiation of a specific wavelength. Radiation from a primary radiation source is directed to a near-field transducer maintained near the disk surface and a radiation detector detects radiation reflected back from the transducer. If the disk has fluorescent material or a metal layer in the nonmagnetic spaces, then a secondary radiation source irradiates the fluorescent material or metal layer with radiation of a specific wavelength to cause the fluorescent material to emit radiation or the metal layer to generate surface plasmons.

Abstract: A patterned-media magnetic recording disk drive uses an optical system for accurately clocking the write data. The disk has concentric data tracks patterned into discrete magnetizable data islands with nonmagnetic spaces between the islands. As the disk rotates, a radiation source directs near-field radiation to the islands and spaces, and a radiation detector receives reflected radiation. The radiation is directed from the source through an optical channel or waveguide on the air-bearing slider that supports the read and write heads. The optical channel or waveguide has a near-field transducer at the disk-facing surface of the slider where the near-field radiation exits and reflected radiation returns. The reflected optical power varies depending on whether the near-field transducer couples to an island or a space, so the radiation detector output signal represents the frequency and phase of the islands as the disk rotates.