144results about "Recording/reproducing/erasing methods" patented technology

This disclosure describes an apparatus that enables rapid transitions during microwave-assisted magnetic recording (MAMR) of storage media. In various aspects, the apparatus incorporates a driver circuit configured to provide a controlled bias current through separate source and sink output terminals, which respond to feedback signals. An MAMR sensor connects between the source and sink output terminals and generates microwave fields when receiving the controlled bias current from the driver circuit. A common-mode feedback (CMFB) loop connects to the source and sink output terminals, detects common-mode voltage (CMV), and delivers feedback signals to the driver circuit to maintain CMV regulation of the MAMR sensor. A differential voltage regulation loop connects to the source and sink output terminals, providing feedback signals that maintain the MAMR sensor voltage differential at a reference value. The apparatus controls the magnetic recording process of the MAMR sensor with rapid transition times.

Mode hop detection is provided. A device includes circuitry to receive, from a reader element an indication of one or more properties of a magnetic medium detected by the reader element. The device includes circuitry to determine an envelope of the signal. The device includes circuitry to adjust, responsive to the envelope, a current provided to a laser configured to heat the magnetic medium.

The embodiment of the invention provides a magnetic tape, a driver, a magnetic tape system and electronic equipment, and aims to avoid failure of the whole magnetic tape system due to breakage of the magnetic tape in the magnetic tape system. The magnetic tape system comprises a magnetic tape, a read-write magnetic head, a page extractor and a controller, the magnetic tape comprises a plurality of storage pages which are arranged in a stacked mode, and in the read-write process of the magnetic tape, the controller can determine at least one target storage page from the storage pages. And then the controller can control the page fetcher to fetch the target storage page and control the read-write magnetic head to read data in the target storage page or write the data into the target storage page. The data is stored in the multiple storage pages, in the working process, the page taking device makes contact with the target storage page so as to take out the target storage page, compared with the mode that a magnetic tape is wound on a reel, the stress of the storage pages is small, and therefore the situation that the magnetic tape in a magnetic tape system breaks, and consequently the whole magnetic tape system fails is avoided.

To improve a thermal gradient of a near-field transducer (NFT) and increase an areal density capacity of a HAMR head.SOLUTION: An NFT includes a main pole (MP) 302, a two-layer transducer 304 positioned adjacent to the MP, a waveguide core 306, and a parabolic waveguide blocker 308 positioned adjacent to the waveguide core, wherein the parabolic waveguide blocker includes a parabolic shape having a surface exposed to an air-bearing surface (ABS) of a write head. The parabolic waveguide blocker reduces electromagnetic radiation from the waveguide core, recycles a scattering field emitted from the NFT to mitigate a thermal background in a recording medium, improves a thermal gradient, and increases an areal density capacity (ADC) of a hard disk drive write head.SELECTED DRAWING: Figure 3A

To provide a magnetic material device capable of suppressing oxidation of the magnetic material, reducing capacitance of a laminated body of the magnetic material, an insulating layer, or conductive layer, and driving at high frequencies.SOLUTION: In a magnetic wire device 60 as a magnetic material device, a magnetic wire 61 and a conducting wire 62 as magnetic materials are arranged via an insulating layer 63. The insulating layer 63 is a laminated body of an insulating non-oxidized film and an insulating oxide film. The insulating non-oxidized film is connected to the magnetic wire 61.SELECTED DRAWING: Figure 6

Provided in the present application are a magnetic recording medium, a positioning method, and a related device. The magnetic recording medium comprises a servo band and a positioning band, wherein the servo band is used for indicating longitudinal position information; and the positioning band is used for indicating physical position information, whch is used for indicating the real physical position of the longitudinal position information in the magnetic recording medium. In the magnetic recording medium, in addition to the existing servo band, a positioning band for indicating physical position information is additionally provided. The physical position information can indicate the real physical position of a certain point, and thus the position information of the magnetic recording medium at the logical level and the position information of the magnetic recording medium at the physical level are interconnected, facilitating physical-level processing on the magnetic recording medium by a user.

Beginning of wrap (BOW) data set reading and writing for tape drives is provided. In response to reaching an end of wrap (EOW) while writing to tape, a tape directory (TD) is updated to include first data set information for a first data set written at the EOW of a first wrap. A second data set is written using normal write procedure from a BOW of a second wrap, the second wrap following the first wrap. The first data set information is overwritten with second data set information for the second data set written at BOW. When reading a BOW data set from tape, data set information is read from a TD. Based on determining whether the data set information corresponds to a BOW data set, a target Data Set ID and a target Tape Write Pass are set for reading the BOW data set.

A dielectric reproducing device and a dielectric recording and reproducing device that can improve the reproduction speed. A detection means is provided so as to be able to detect a polarization state of each bit 1a corresponding to the data recorded in a data recording layer by relatively scanning the data recording layer made of a dielectric material. A heating means is provided so as to be able to heat the bit to be detected to a predetermined temperature while the detection means detects the polarization state. A reproducing means is provided so as to be able to reproduce the data based on the polarization state of each bit detected by the detection means.

According to one embodiment, a magnetic disk device includes a disk, a write head, a write processing unit, an error correction unit, a correction limit prediction unit, and a determination unit. During a write period in which the write processing is executed on the second data track, the correction limit prediction unit is capable of determining whether or not data of each of the target sectors of the first data track is damaged, and generates prediction information, and the determination unit determines whether or not to cause the write processing unit to continue the write processing on the second data track based on the prediction information.

Various methods and systems are provided for implementing classification-based adjustable seek energy settings in storage device systems. In particular, operations support adjusting seek energy settings for storage device components, for executing requests. In operation, a classification is selected for a request. The classification indicates a first priority level for executing the request. The priority level is associated with a first adjustable seek energy setting of a plurality adjustable seek energy settings for executing requests on the hard disk drive system, where a seek energy setting is an adjustable operational speed or energy setting for the hard disk drive system. Based on the classification indicating the priority level, the classification is transmitted to cause the hard disk drive system to set the adjustable seek energy setting. One or more hardware components of the hard disk drive system operates to execute the first request based on the first adjustable seek energy setting.

The purpose of this disclosure is to provide a heat-assisted magnetic recording (HAMR) writer head with high magnetic field reliability and high accuracy. [Solution] Disclosed are a writer head for a heat-assisted magnetic recording device and a method for manufacturing a writer head. The writer head comprises a plurality of layers, including a waveguide cutoff layer, a waveguide layer, a near-field transducer layer, a heat sink layer, and a peg layer. Each layer has a tapered angle near the air bearing surface. The writer head further has a principal axis pole adjacent to an optical component having a similar tapered angle near the air bearing surface.

Provided is a magnetic recording device capable of achieving an increase in recording density. According to an embodiment, the magnetic recording device includes a magnetic head and a control section. The magnetic head includes a first magnetic pole, a magnetic element, and a coil, and the magnetic element includes a magnetic layer. The control section is electrically connected to the magnetic element and the coil. The control section is capable of supplying a recording current to the coil and an element current to the magnetic element. The recording current includes a first period of a first polarity, a second period of a second polarity different from the first polarity, a third period of transition from the first period to the second period, and a fourth period of transition from the second period to the first period. The element current includes a direct current component and an alternating current component. The alternating current component in the first period is the same as the alternating current component in the second period, the alternating current component in the third period, and the alternating current component in the fourth period.

To provide a method for producing a magnetic recording medium capable of having a magnetic layer with high crystal orientation and few defects, a magnetic recording medium, and a magnetic storage device.SOLUTION: A method of producing a magnetic recording medium 1 includes: a step of forming a magnesium oxide underlayer 20 on a surface of a substrate 10 by a sputtering method with using a target containing magnesium oxide; and a step of forming a magnetic layer 30 on the surface side of the magnesium oxide underlayer 20, in which the target containing the magnesium oxide is heated to more than 600°C when forming the magnesium oxide underlayer 20.SELECTED DRAWING: Figure 1

A Data Storage Device (DSD) comprises a magnetic disk and a slider including a writer configured to magnetically write data on the magnetic disk. A voltage is applied to the slider to provide a target offset voltage between the slider and the magnetic disk with the applied voltage differing from a disk voltage of the magnetic disk. In one aspect, a first disk voltage is determined for the magnetic disk. The voltage to be applied to the slider is determined to adjust an electric potential difference between the slider and the disk to the non-zero target offset voltage. In another aspect, the voltage applied to the slider is less than the disk voltage and reduces deterioration of the slider caused by operation of an energy-assisted magnetic recording technology at the slider while maintaining a safe fly height of the slider over the magnetic disk.

A magnetic disk device capable of improving data recording performance is provided. The magnetic disk device includes: a magnetic disk; a magnetic head; a power supply unit that supplies power to the magnetic head; a control unit that controls reading and writing data from the magnetic disk and, when writing data, suppresses the magnetic field range of the write head based on the offset of the write head; and an address storage unit that stores the address of the magnetic disk where data was written with the magnetic field range suppressed. The control unit reads data from the magnetic disk using the read head at a predetermined timing based on the address stored in the address storage unit, and writes the read data to the magnetic disk using the write head without suppressing the magnetic field range.

Various illustrative appearances relate to a data storage device, a method, and one or more processing devices configured to: open a servo gate in the selected head during a read operation to read the first servo bursts, the sync mark, and the second servo bursts in one of the servo sectors; and determine a position error signal for the selected head based on reading the first servo bursts and the second servo bursts.

The present disclosure describes aspects of a differential current-mode (iMode) driver for microwave-assisted magnetic recording (MAMR) application in hard-disk drives. In some aspects, an iMode driver circuitry employs a driver circuit coupled to power supply connections. The driver circuit is configured to provide a controlled differential bias current and includes separate source and sink output terminals. A MAMR sensor couples between the source and sink output terminals, through which the MAMR sensor receives the controlled differential bias current provided by the driver circuit. The MAMR sensor, which has a field-entry terminal and a field-exit terminal, generates microwave fields for the recording process. A common-mode feedback (CMFB) loop couples to the field-entry and field-exit terminals of the MAMR sensor, forming a feedback pathway with the driver circuit. This CMFB loop detects common-mode voltage (CMV) and adjusts the controlled differential bias current to maintain CMV regulation of the MAMR sensor.

According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a magnetic element. The magnetic element is provided between the first magnetic pole and the second magnetic pole in a first direction from the first magnetic pole to the second magnetic pole. The magnetic element includes a first magnetic layer provided between the first magnetic pole and the second magnetic pole, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a third magnetic layer provided between the second magnetic layer and the second magnetic pole, and a fourth magnetic layer provided between the third magnetic layer and the second magnetic pole. The first magnetic layer includes a first face facing the first magnetic pole. The fourth magnetic layer includes a second face facing the second magnetic pole.

A magnetic disk device and a read / write processing method capable of increasing track density are provided. The magnetic disk device and the read / write processing method according to this embodiment include: a disk; a head for writing data to and reading data from the disk; and a controller for writing to a second track overlapping with a first track in a radial direction of the disk; performing a first replacement process of recording a first user sector usable by a user in a first area when a first user sector cannot be written in the first track; and performing a second replacement process, different from the first replacement process, of recording the first parity sector in a second area when a first parity sector obtained by performing an XOR operation cannot be written in the first track.

Described are write head constructions that may be useful in magnetic recording, and in particular for heat-assisted magnetic recording. Such write head constructions include a heat channel abutted to the write pole to facilitate transferring heat away from the write pole and other components near the media-facing surface of the write head. To help prevent diffusion of materials between the heat channel and the write pole, a diffusion barrier layer is provided. Properties such as thermal expansion mismatch, the presence of oxide in the diffusion barrier layer, and so forth, may lead to undesired delamination of the heat channel during fabrication of the write head and / or during operation. In accordance with the present disclosure, an adhesion layer may be provided between the diffusion barrier layer and the heat channel to improve adhesion of the heat channel and effectively reduce delamination.

To provide a detection device, an inspection device, a magnetic tape drive, a magnetic tape system, a detection method, an inspection method, and a program capable of accurately detecting a servo pattern signal even if there are variations in geometric characteristics of a servo pattern.SOLUTION: A detection device includes a processing device and a storage medium. The storage medium stores an ideal waveform signal in advance representing an ideal waveform of a servo pattern signal resulting from reading of the servo pattern recorded on a servo band of a magnetic tape by a servo reading element. The processing device obtains the servo band signal resulting from reading of the servo band by the servo reading element and detects the servo pattern signal by comparing the servo band signal and the ideal waveform signal.SELECTED DRAWING: Figure 10

To provide a magnetic recording device that enables improved recording density. [Solution] According to the embodiment, the magnetic recording device includes a magnetic head and a control unit. The magnetic head includes first and second magnetic poles, a magnetic element, and a coil. The control unit is configured to switch between performing a first operation and a second operation. In the first operation, the control unit supplies a first recording element current to the magnetic element. In the second operation, the control unit supplies a second recording element current to the magnetic element. The first recording element current is less than or equal to a first current value. The second recording element current exceeds the first current value.

Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: during a read operation, open a servo gate in the selected head in order to read the first servo bursts, the sync mark, and the second servo bursts in one of the servo sectors; and determine a position error signal for the selected head based on reading the first servo bursts and the second servo bursts.

The embodiment of the invention relates to a magnetic disk device. A magnetic disk device includes a disk, a write head, a write processing unit that selects a shingled recording type and causes the write head to execute writing of data to each tape (BA), a determination unit, and a refresh processing unit. The determination unit determines whether or not a quality degradation recording sector (DRSC) exists in all recording sectors (RSC) in each band (BA). And a refresh processing unit that refreshes the plurality of target recording sectors (TSC) when it is determined that there is a target band (TBA) including the quality degradation recording sector (DRSC) among the plurality of bands (BA). The plurality of object recording sectors (TSC) includes a quality degradation recording sector (DRSC). In the object tape (TBA), the number of the plurality of object recording sectors (TSC) is smaller than the number of all recording sectors (RSC).

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.

Disclosed are methods for linearizing the response of a non-linear magnetic reader, for example in the operation of a hard disk drive. Magnetic readers generally exhibit non-linearities in their response to an applied magnetic field, and those non-linearities may be particularly pronounced when the field strength is high. This deviation from linearity at larger field strengths can limit the useful range of field amplitudes. To expand the useful range of field amplitudes and thereby increase the available signal at the reader, the reader bias current may be varied in such a way to compensate for the natural non-linearity of the reader, thus making the reader output signal linear over a larger range of detected field strengths.

A method according to one embodiment includes acquiring a result of quality inspection related to recording quality of first sectors included in a first storage area of a magnetic disk. The method includes calculating a first number being the number of sectors corresponding to a capacity obtained by subtracting a set capacity from an actual capacity of the first storage area. The first number is calculated based on the set capacity of the first storage area and a set value of recording density of the first storage area. The method includes selecting a second number of sectors from the first sectors based on the result of quality inspection. The method includes assigning addresses to a group of sectors that are not included in the second number of sectors among the first sectors. The group of sectors consists of sectors with the number corresponding to the set capacity.