Encoding techniques for patterned magnetic media
View Patent ↗The invention is directed to patterned magnetic media for use in magnetic recording and data storage, and various encoding techniques that can be used to magnetically encode data on the patterned media. For example, a patterned magnetic recording medium can include a first set of surface variations and a second set of surface variations. The medium can be conditioned to magnetically expose the surface variations relative to areas between the respective surface variations. Detection of the surface variations in the first set can allow for synchronization of a magnetic drive to the medium. Following such synchronization, the magnetic drive can selectively apply magnetic fields to a second set of surface variations of the patterned magnetic medium to encode data on the patterned magnetic medium.
1. A method comprising:
synchronizing a magnetic drive to a patterned magnetic medium based on detection of a set of first surface variations in the patterned magnetic medium; and
selectively applying magnetic fields to a second set of surface variations of the patterned magnetic medium to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium, wherein the first and second sets of surface variations comprise first and second protrusions respectively, and selectively applying magnetic fields to the second set of surface variations comprises applying magnetic fields to the second protrusions and not applying magnetic fields to areas between the second protrusions.
2. A method comprising:
synchronizing a magnetic drive to a patterned magnetic medium based on detection of a set of first surface variations in the patterned magnetic medium; and
selectively applying magnetic fields to a second set of surface variations of the patterned magnetic medium to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium;
the method further comprising conditioning the magnetic medium prior to synchronizing the magnetic drive to magnetically expose the first and second sets of surface variations relative to areas between the surface variations in the first set and areas between the surface variations in the second set.
3. A method comprising:
synchronizing a magnetic drive to a patterned magnetic medium based on detection of a set of first surface variations in the patterned magnetic medium; and
selectively applying magnetic fields to a second set of surface variations of the patterned magnetic medium to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium, wherein the patterned magnetic medium exhibits perpendicular magnetic anisotropy, and at least some of the surface variations in the first and second sets define widths of less than approximately 5.0 microns.
4. The method of claim 3 , wherein at least some of the surface variations in the first and second sets define widths of less than approximately 1.0 micron.
5. A method comprising:
synchronizing a magnetic drive to a patterned magnetic medium based on detection of a set of first surface variations in the patterned magnetic medium;
selectively applying magnetic fields to a second set of surface variations of the patterned magnetic medium to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium; and
magnetically detecting the set of first surface variations relative to areas between the surface variations in the first set.
6. A method comprising:
synchronizing a magnetic drive to a patterned magnetic medium based on detection of a set of first surface variations in the patterned magnetic medium; and
selectively applying magnetic fields to a second set of surface variations of the patterned magnetic medium to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium, wherein synchronizing the magnetic drive includes identifying a variable frequency oscillator (VFO) signal in the set of first surface variations.
7. A system comprising:
a patterned magnetic recording medium including a substrate, and a magnetic recording layer formed over the substrate, the magnetic recording layer including a first set of surface variations and a second set of surface variations; and
a magnetic drive that synchronizes to the patterned magnetic medium based on detection of the set of first surface variations, and selectively applies magnetic fields to the second set of surface variations to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium, wherein the magnetic head includes a magnetic head positiond relative to the patterned magnetic recording medium and a controller to control application of magnetic fields by the magnetic head, and wherein the magnetic head defines a gap less than approximately 50% of a width associated with the surface variations in the second set.
8. A system comprising:
a patterned magnetic recording medium including a substrate, and a magnetic recording layer formed over the substrate, the magnetic recording layer including a first set of surface variations and a second set of surface variations; and
a magnetic drive that synchronizes to the patterned magnetic medium based on detection of the set of first surface variations, and selectively applies magnetic fields to the second set of surface variations to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium, wherein the first and second sets of surface variations comprise first and second protrusions respectively, and the magnetic drive selectively applies magnetic fields to the second set of surface variations by applying magnetic fields to the second protrusions and not applying magnetic fields to areas between the second protrusions.
9. A system comprising:
a patterned magnetic recording medium including a substrate, and a magnetic recording layer formed over the substrate, the magnetic recording layer including a first set of surface variations and a second set of surface variations; and
a magnetic drive that synchronizes to the patterned magnetic medium based on detection of the set of first surface variations, and selectively applies magnetic fields to the second set of surface variations to encode data on the patterned magnetic medium, wherein a timing of the selective application of the magnetic fields is defined by the synchronization of the magnetic drive to the patterned magnetic medium, wherein the patterned magnetic recording medium exhibits perpendicular magnetic anisotropy and at least some of the surface variations in the first and second sets define widths of less than approximately 5.0 microns.