Patent classifications
G11B11/10506
Non-contact laser-induced protrusion measurement apparatus and method
A method and apparatus are directed to providing relative movement between a slider configured for heat-assisted magnetic recording and a magnetic recording medium, and causing protrusion of a portion of an air bearing surface (ABS) of the slider in response to activating at least a laser source while maintaining spacing between the protrusion and the medium. A magnitude of at least a portion of the protrusion is measured while maintaining spacing between the protrusion and the medium.
Adjacent track interference asymmetry mitigation
A storage device includes a controller that selects an offset when preparing to write data to a target data track. The offset defines a position for a write head relative to a center of the target track and is selected based on a radial position of a write head at the target data track.
Polynomial spiral waveguide that facilitates coupling light to a near-field transducer at an oblique angle
A recording head includes a near-field transducer located an oblique angle to a media-facing surface. The near-field transducer includes an enlarged portion and a peg extending from the enlarged portion towards the media-facing surface at a normal angle. An input waveguide of the recording head receives energy from an energy source, and an output waveguide delivers the energy to near-field transducer at the oblique angle. The output waveguide is oriented at the oblique angle. A bent waveguide with a polynomial spiral shape joins the input waveguide and the output waveguide.
Near field transducer having an adhesion layer coupled thereto
A system, according to one embodiment, includes a near field transducer; an adhesion layer on a media facing side of the near field transducer, the adhesion layer comprising Ni and Cr; and a protective layer on a media facing side of the adhesion layer. Other systems and methods are described in additional embodiments.
Interlaced magnetic recording super parity
A storage device includes a storage medium having a first set of non-adjacent data tracks having a number of super parity sectors and a second set of non-adjacent data tracks interlaced with the first set of non-adjacent data tracks. The number of super parity sectors on a data track of the first set of non-adjacent data tracks is selected based on a distance between the data track and an inner diameter of the storage medium.
Enhanced capacity recording
A storage device includes a storage controller configured to write a band of data tracks using a first recording method until criterion is met. The first method may be a conventional recording method. After the criterion is met, the storage controller is configured to write data to the band using a second recording method. The second recording method may be an enhanced capacity recording method such as interlaced magnetic recording (IMR) or shingled magnetic recording (SMR).
Determining write-induced protrusion as a function of laser power using temperature measurements
A test involves iterations over a series of laser powers of a heat-assisted read/write head. The iterations involve writing to a recording medium at the selected laser power for a sufficient duration to ensure thermal equilibrium of the read/write head at an end of the write. A clearance-control heater of the read/write head is transitioned from a pre-write power before a start of the write to a steady-state write power. The iterations further involve measuring a temperature of the read/write head during the write and adjusting the steady-state write power to achieve a predefined difference between the temperature at the start of the write and the end of the write. The adjusted steady state write power is stored for each iteration. A write-induced protrusion is determined based on the iterations and used for calibration of the read/write head.
NEAR-FIELD TRANSDUCER WITH TAPERED PEG
An apparatus includes a waveguide that delivers energy from an energy source, a write pole located proximate the waveguide at a media-facing surface, and a near-field transducer located proximate the write pole in a down track direction. The near-field transducer includes an enlarged portion and a peg extending from the enlarged portion towards the media-facing surface. The peg comprises a taper facing away from the write pole, and the taper causes a reduced down track dimension of the peg near the media-facing surface.
Optical magnetic recording system, writer, media, and method
Described are optical magnetic recording systems, writers, media, and methods that utilize pulses of electromagnetic radiation to deterministically record information on magnetic storage media unaided by any additionally applied magnetic field such as from a write pole. The recording pulses may be linearly (or longitudinally) polarized pulses or circularly polarized pulses. The pulses may be modulated in accordance with data bits to be written on the media. Modulation may include modulating the polarization state(s) of the pulses and/or modulating the amplitude(s) the pulses, depending on the particular construction or configuration of the magnetic storage media to be used. Described are recording systems and methods that include laser light pulse generation, light pulse modulation, light pulse delivery, and magnetic media constructions.
Magnetic media
A magnetic medium is described which includes a thin film magnet structure formed of a ferromagnetic alloy or compound. The thin film magnet structure includes one or more ferromagnetic domains and is coupled to one or more optical structures. Each of the one or more ferromagnetic domains have a magnetization that is switchable between two or more states. Each of the one or more optical structures is configured to increase absorbance of light at a target wavelength in the thin film magnet structure, such that in response to illumination of a ferromagnetic domain with continuous-wave light including the target wavelength, that ferromagnetic domain undergoes all-optical magnetic switching.