Abstract: An apparatus comprises a spindle to rotate a magnetic recording medium and a magnetic field generator to expose a track of the medium to a DC magnetic field. The magnetic field generator is configured to saturate the track during an erase mode and reverse the DC magnetic field impinging the track during a writing mode. A laser arrangement heats the track during the erase mode and, during the writing mode, heats the track while the track is exposed to the reversed DC magnetic field so as to write a magnetic pattern thereon. A reader reads the magnetic pattern and generates a read signal. A processor is coupled to the reader and configured to measure one or more magnetic properties of the track using the read signal. The apparatus can further comprise a Kerr sensor that generates a Kerr signal using the magnetic pattern.

Abstract: A method, apparatus, and system are provided for implementing a write head device for writer-to-disk contact detection and spacing sensing of recording heads in hard disk drives (HDDs). A write head device, such as a spin-torque oscillator (STO), is provided between a main pole tip and a surrounding magnetic shield of the writer in the recording head. A pair of connections is provided to the magnetic shield and the main pole of the writer, and resistance of the write head device is measured to detect writer to disk spacing and contact.

Abstract: A device including a waveguide, the waveguide having a first portion where energy having a wavelength, ?, enters and a second portion where the energy exits, the waveguide including a core layer with an index of refraction, n1; at least one cladding layer formed adjacent the core layer, the cladding layer having an index of refraction, n2; a reflective layer, the reflective layer positioned adjacent the first portion of the waveguide; and an interlayer, the interlayer positioned between the first portion of the waveguide and the reflective layer, the interlayer having an index of refraction, n3; wherein n3 is greater than n2.

Abstract: A method and system provide a near-field transducer (NFT) for an energy assisted magnetic recording (EAMR) transducer. The method and system include forming an NFT having a disk and a pin. A dielectric layer that substantially covers the NFT is deposited. A portion of the dielectric layer is removed such that the dielectric layer has an aperture therein. The aperture exposes the pin of the NFT. The EAMR transducer is annealed at a temperature greater than the expected operating temperature of the EAMR transducer.

Abstract: A method, apparatus and computer-readable recording medium are disclosed, for recording information in an information recording medium. The method includes a first step of outputting, in response to an initialization request for initializing the information recording medium, termination information indicative of termination of the initialization before the initialization starts, and a second step of starting the initialization at a predetermined timing after the output of the termination information. In this procedure, it is possible to start to record data in a blank disc sooner than in conventional methods.

Abstract: An optical information recording and reproducing apparatus includes an irradiation unit of a signal light beam and a reference light beam required for data recording, and a cure irradiation unit having at least one of a pre-cure irradiation that irradiates a predetermined light beam on to a desired position prior to irradiating the reference light bean and the signal light beam on to the desired position when information is recorded in the desired position on an optical information recording medium and a post-cure irradiation that irradiates a predetermined light beam on to the desired position so as to make the desired position non-recordable after the information is recorded in the desired position on the recording medium. The cure irradiation unit is disposed in one driving device in a freely movable manner in the driving device.

Abstract: An apparatus, system, and method for measuring thermally induced electric resistance changes in thermally assisted magnetic recording are disclosed for monitoring laser light output in thermally assisted magnetic recording disk drives. An electrical lead is coupled to a read/write head element. A first electrical resistance in the read/write head element is measured. The read/write head is heated by a laser and a second electrical resistance in the read/write head element is measured. The electrical resistance may be monitored at regular intervals when the read/write head element is on the ramp or the electrical resistance measurements may be continuously monitored as the read/write head flies over the magnetic media.

Abstract: A method of manufacturing a plasmon generator includes the steps of forming an accommodation part and forming the plasmon generator to be accommodated in the accommodation part. The step of forming the accommodation part includes the steps of: forming a dielectric layer having an upper surface; etching the dielectric layer by using an etching mask and thereby forming a groove in the dielectric layer; and forming a dielectric film in the groove. The groove has first and second sidewalls and a bottom. Each of the first and second sidewalls forms an angle in the range of 0° to 15° relative to the direction perpendicular to the upper surface of the dielectric layer. The dielectric film includes a first portion interposed between the first sidewall and the first side surface, and a second portion interposed between the second sidewall and the second side surface.

Abstract: Incident light can be efficiently converted into near-field light whose spot size is small. A waveguide 10 includes: a metallic member 11 made of a metallic material; and a dielectric member 12 made of a dielectric material. The metallic member 11 includes a first interface 16 and a second interface 18 so as to sandwich the dielectric member 12. The first interface and the second interface are provided so that an inter-interface distance therebetween may decrease from ends 16c and 18c to ends 16d and 18d. The first interface 16 and the second interface 18 have flections P16 and P18, respectively.

Abstract: A heat-assisted magnetic recording head includes a slider, and an edge-emitting laser diode that emits polarized light of TM mode. The laser diode is arranged so that its bottom surface faces the top surface of the slider. An electrode of the laser diode closer to the active layer is bonded to a conductive layer of the slider, whereby the laser diode is fixed to the slider. As viewed from above the laser diode, the bottom surface of the electrode of the laser diode includes a first area that a light propagation path of the laser diode overlies, and a second area other than the first area. The top surface of the conductive layer is in contact not with the first area but with the second area of the bottom surface of the electrode.

Abstract: An apparatus includes a recording media including a substrate, a plurality of tracks of magnetic material on the substrate, and a non-magnetic material between the tracks; a recording head having an air bearing surface positioned adjacent to the recording media, and including a magnetic pole, an optical transducer, and a near-field transducer, wherein the near-field transducer directs electromagnetic radiation onto tracks to heat portions of the tracks and a magnetic field from the magnetic pole is used to create magnetic transitions in the heated portions of the tracks; and a plasmonic material positioned adjacent to the magnetic material to increase coupling between the electromagnetic radiation and the magnetic material.

Abstract: A thermally assisted magnetic head includes a main magnetic pole for writing and a near-field light generator provided near the main magnetic pole, the near-field light generator having a non-magnetic base metal layer, a non-magnetic upper metal layer, an intermediate insulating layer interposed between the base metal layer and the upper metal layer, and the base metal layer having a V-shaped groove and also the upper metal layer having a projection facing the deepest part in the groove of the base metal layer, in a vertical cross-section parallel to a medium facing surface.

Abstract: An optical device includes a clad composed of a material having a first refractive index, a core which is embedded in the clad, composed of a material having a second refractive index different from the first refractive index, and tapers toward the end-point thereof, and a light-transmitting layer which is composed of a material different from the material having the second refractive index and cuts across an optical path at the end-point thereof.

Abstract: When carrying out magnetization, annealing, and initialization of a recording film by applying a laser beam to the recording film while rotating an optical recording medium 10 by a motor 11, light of a strong visible-light lamp 15 is projected as parallel light to a reflecting mirror 14 via a lens 16 so as to apply light reflected by the reflecting mirror 14 to an area wider than a spot of the laser beam on the medium 10 for heating. At that time, a control unit 18 controls an intensity of the strong visible-light lamp 15 to raise a temperature of the medium 10 to a temperature of 80° C. or higher and a softening point of a substrate or lower, for example.

Abstract: A magneto-optical recording or reproducing device having an information erasing means for erasing information or data recorded on a magneto-optical recording medium. According to the invention, the information erasing means comprises an erasing magnet having a field strength sufficient to initialize the magneto-optical recording medium without the assistance of a laser and/or an optical scanning device.

Abstract: A magnetooptic recording medium has at least a recording layer for recording data and a reproducing layer for reproducing the data recorded in the recording layer onto a substrate and reproduces the data by setting a proper reproducing laser power upon reproduction. According to the magnetooptic recording medium, magnetizing directions of a buffer area, a sector address area, and a gap area which are sandwiched between data areas in which the data is recorded are uniformly magnetized in the recording direction.

Abstract: An optical disk of the present invention includes a substrate and a recording layer disposed above the substrate, and reproduces an information signal by a DWDD system, using light incident from the substrate side. The optical disk further includes a first dielectric layer disposed between the substrate and the recording layer and a second dielectric layer disposed on the recording layer opposite to the substrate, wherein the recording layer is initialized with light having a wavelength ? incident from the second dielectric layer side, and the thickness of the second dielectric layer is in a range of ?/(12×n) to ?/(2×n) (where n is a refractive index of the second dielectric layer).

Abstract: A magnetooptic recording medium has at least a recording layer for recording data and a reproducing layer for reproducing the data recorded in the recording layer onto a substrate and reproduces the data by setting a proper reproducing laser power upon reproduction. According to the magnetooptic recording medium, magnetizing directions of a buffer area, a sector address area, and a gap area which are sandwiched between data areas in which the data is recorded are uniformly magnetized in the recording direction.

Abstract: The object of the present invention is to realize reduction of the level jitter generated from a noise component at a signal saturation level or a waveform distortion in a portion except for signal polarity portions (rising edge and falling edge), and good error characteristics. In the present invention, a predetermined upper or lower limit value is set to reproduction signals, the reproduction signals are subjected to a limiter processing for correcting reproduction signals of the upper limit value or more, or the lower limit value or less to the level of the upper limit value or the lower limit value, respectively, the signal subjected to the limiter processing is subjected to a partial response equalizing (PR equalizing) processing, and PR reproduction is performed to improve the level jitter at PR detection time and the error rate at information reproduction time.

Abstract: A magneto-optical disk of the present invention includes a substrate and a recording layer disposed above the substrate, and reproduces an information signal by a DWDD system, using light incident from the substrate side. The optical disk further includes a first dielectric layer disposed between the substrate and the recording layer and a second dielectric layer disposed on the recording layer opposite to the substrate, wherein the recording layer is initialized with light having a wavelength &lgr; incident from the second dielectric layer side, and the thickness of the second dielectric layer is in a range of &lgr;/(12×n) to &lgr;/(2×n) (where n is a refractive index of the second dielectric layer).

Abstract: The present invention provides an information storage apparatus which at least records information by applying a magnetic field to a recording medium with a smaller power consumption. A default value of a recording magnetic field is set to a minimum value of the apparatus. Through a learning process, the default value of the recording magnetic field is changed to a value in the vicinity of the minimum value.

Abstract: A system and method for initializing large portions, or extents, of a mass-storage device in the background so that such overwriting processes do not significantly affect latency as experienced by a host. The method extends the use a system intended for background copying of data from a source extent to a destination extent to that of initializing an extent on a mass-storage device. It does so by causing the system to treat the defined extent as both a source extent and as a destination extent simultaneously.

Abstract: A method of initializing a phase-change optical information recording medium is provided, using an optical system incorporating a semiconductor laser device. The laser device is characterized by a specified spatial power distribution. In a spatial distribution of the laser power focused on the recording medium, in the direction perpendicular to guide tracks the laser device preferably has less average smaller in both end regions of the spatial distribution, which have each 10% of the width at half maximum of the distribution, than the average in the center region of the full width at half maximum of the distribution.

Abstract: A method of initializing a phase-change optical information recording medium is provided, using an optical system incorporating a semiconductor laser device. The laser device is characterized by a specified spatial power distribution. In a spatial distribution of the laser power focused on the recording medium, in the direction perpendicular to guide tracks the laser device preferably has less average smaller in both end regions of the spatial distribution, which have each 10% of the width at half maximum of the distribution, than the average in the center region of the full width at half maximum of the distribution.