32results about "Special recording techniques" patented technology

To provide a ferroelectric storage device capable of stabilizing a torque of a ferroelectric recording medium drive unit even when used for a long time and suppressing a decrease in continuity in the ferroelectric recording medium drive unit.SOLUTION: A ferroelectric storage device according to the present invention includes a ferroelectric recording medium, a conductive probe, a probe slider, and a ferroelectric recording medium drive unit. The ferroelectric recording medium drive unit has a bearing sleeve inside a housing and a conductive shaft member inserted into an inner peripheral surface of the bearing sleeve, a gap between the inner peripheral surface of the bearing sleeve and an outer peripheral surface of the shaft member contains lubricating oil that generates pressure by dynamic pressure to support the shaft member in a radial direction in a non-contact manner, the housing has a conductive housing bottom portion that faces the shaft end of the shaft member, a convex or concave spherical surface is included on at least one of the shaft end portions of the shaft member and the bottom portion of the housing, and the lubricating oil contains a conductive powder containing an inorganic material.SELECTED DRAWING: Figure 8

A data storage device comprises a magnetic medium and a head configured to be actuated over the magnetic medium. The head comprises a write element and a write driver configured to generate a write current to be applied to the write element. The write driver comprises a data switch section configured to switchably output low-level signals and high-level signals, and a stationary cascode section configured to receive the low-level signals and high-level signals from the data switch section and to generate a cascode pass through current. The data switch section comprises low voltage CMOS devices and the stationary cascode section comprises high voltage CMOS devices.

To provide a ferroelectric storage device, a method for reading information in the ferroelectric storage device, and a method for writing and reading information in the ferroelectric storage device that can read information stored in a ferroelectric recording medium at a high speed.SOLUTION: A ferroelectric storage device according to the present invention comprises: a ferroelectric recording medium that has a ferroelectric layer; a conductive probe; a probe slider; a ferroelectric recording medium driving unit; and a recording reproduction signal processing unit that is connected with the conductive probe and performs processing on an information writing signal and an information reading signal. In detecting an electric charge on the ferroelectric layer, the recording reproduction signal processing unit applies positive and negative bias voltages to the conductive probe, and measures a tunnel current flowing between the conductive probe and the ferroelectric layer to detect the electric charge on the ferroelectric layer.SELECTED DRAWING: Figure 10

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.

A ferroelectric recording medium includes an electrode layer, a ferroelectric recording layer, and a protection layer formed in this order on a substrate, wherein the ferroelectric recording layer includes a ferroelectric layer, and a lattice constant of a material constituting the ferroelectric layer and a lattice constant of a material constituting the electrode layer or the substrate are lattice-matched within a range of ±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.

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.

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, a coil, a first terminal, and a second terminal. The control unit is configured to perform a first operation. In the first operation, the control unit is configured to supply a recording element current to the magnetic element and a recording coil current to the coil. The absolute value of the recording coil current is less than or equal to the first coil current value corresponding to the first peak.

The present disclosure provides a magnetic recording device capable of improving recording density. According to one embodiment, a magnetic recording apparatus includes a magnetic head and a control unit. The magnetic head includes a first magnetic pole, a second magnetic pole, a magnetic element, a coil, a first terminal, and a second terminal. The control unit is configured to perform a first operation. In the first operation, the control unit supplies a recording-time element current to the magnetic element and supplies a recording-time coil current to the coil. The absolute value of the coil current during recording is equal to or less than a first coil current value corresponding to the first peak.

To provide a ferroelectric storage device that can read information stored in a ferroelectric recording medium at a high speed.SOLUTION: A ferroelectric storage device according to the present invention comprises: a ferroelectric recording medium; a conductive probe that performs writing and reading of information with respect to the ferroelectric recording medium; a probe slider that causes the conductive probe to move in a floating state on a surface of the ferroelectric recording medium; a ferroelectric recording medium driving unit that rotates the ferroelectric recording medium; and a recording reproduction signal processing unit that performs processing on an information writing signal and an information reading signal with the conductive probe. The recording reproduction signal processing unit detects a signal generated due to interatomic force between the conductive probe and the ferroelectric recording medium.SELECTED DRAWING: Figure 8

To provide a thermally assisted magnetic recording / reproducing device in which a lubricant hardened material is provided in advance near a near field optical element in a head while minimizing impact on areas other than an area where a lubricant hardened material is formed, and an adjustment method thereof.SOLUTION: An adjustment method of a thermally assisted magnetic recording / reproducing device according to the embodiment includes: maintaining a thermally assisted magnetic recording head of the thermally assisted magnetic recording / reproducing device on-track; maintaining a record current for data recording for the thermally assisted magnetic recording head that is less than a threshold value; and applying a light source drive current for light emission to a light source.SELECTED DRAWING: Figure 5

To provide a ferroelectric storage device capable of controlling a distance between a probe and a recording medium with high accuracy and high speed.SOLUTION: A ferroelectric storage device according to the present invention includes: a ferroelectric recording medium; a conductive probe; a probe slider; a piezoelectric element or an electrostrictive element which is provided on the probe slider and in which the conductive probe is connected so as to face the ferroelectric recording medium; and a control unit that controls a voltage applied to the piezoelectric element or the electrostrictive element to expand and contract the piezoelectric element or the electrostrictive element and adjusts a distance between the ferroelectric recording medium and the conductive probe. The control unit controls the voltage applied to the piezoelectric element or the electrostrictive element based on a read signal from the conductive probe to expand and contract the piezoelectric element or the electrostrictive element.SELECTED DRAWING: Figure 9

The embodiment of the invention relates to a heat-assisted magnetic recording and reproducing apparatus and an adjusting method thereof. In the method of adjusting a heat-assisted magnetic recording and reproducing apparatus according to an embodiment, a heat-assisted magnetic recording head of the heat-assisted magnetic recording and reproducing apparatus is maintained in orbit, a recording current for data recording is maintained to be less than a threshold value for the heat-assisted magnetic recording head, and a light source driving current for emitting light is applied to a light source.

A method of forming a read head is described where a Tunneling Magnetoresistive (TMR) stack of layers comprised of a free layer (FL) and having sidewalls separated by a cross-track width is formed on a bottom shield. In subsequent steps, a first insulation layer and longitudinal biasing layer are formed on the sidewalls and bottom shield. After a TMR sensor backside is formed that exposes the bottom shield, a second insulation layer and permanent magnet (PM) layer are deposited on exposed portions of the bottom shield. Thereafter, the PM layer magnetization is initialized in a direction that adjusts FL bias point, and shifts sensor asymmetry (Asym) closer to 0% for individual heads at slider or Head Gimbal Assembly level to provide a significant improvement in device yield. Asym is adjusted using different initialization schemes and initialization directions. With individual heads, initialization direction is selected based on a prior asymmetry measurement.

According to one embodiment, a magnetic recording device includes a magnetic recording medium, a plurality of magnetic heads for recording information on the magnetic recording medium, and a controller for controlling the magnetic heads. Each of the magnetic heads includes a coil, a first magnetic pole for generating a magnetic field according to a recording current supplied to the coil, and a light emitting section for irradiating the magnetic recording medium with light to locally increase a temperature of the magnetic recording medium. The controller performs a first operation, in which a lifetime information related to a remaining life time of one of the magnetic heads is calculated based on a first information related to a failure probability of a magnetic head group including the magnetic heads and a second information related to a remaining time based on a history of the one of the magnetic heads.

A data storage device comprises a magnetic medium and a head configured to be actuated over the magnetic medium. The head comprises a write element and a write driver configured to generate a write current to be applied to the write element. The write driver comprises a data switch section configured to switchably output low-level signals and high-level signals, and a stationary cascode section configured to receive the low-level signals and high-level signals from the data switch section and to generate a cascode pass through current. The data switch section comprises low voltage CMOS devices and the stationary cascode section comprises high voltage CMOS devices.

To provide a ferroelectric storage device that can achieve improvement of recording capacity and acceleration of speed required for recording and reproduction of information.SOLUTION: A ferroelectric recording medium according to the present invention comprises: a ferroelectric recording medium; a conductive probe that performs writing and reading of information with respect to the ferroelectric recording medium; a probe slider that causes the conductive probe to move in a floating state on a surface of the ferroelectric recording medium; a ferroelectric recording medium driving unit that rotates the ferroelectric recording medium; and a recording reproduction signal processing unit that performs processing on an information writing signal and an information reading signal with the conductive probe. The probe slider is provided with a piezoelectric element or an electrostrictive element for moving the conductive probe in a track direction of the ferroelectric recording medium.SELECTED DRAWING: Figure 10

To provide a ferroelectric storage device that can achieve improvement in recording density, reduction in a size per unit storage capacity, and acceleration of a speed required for recording and reproduction of information, and can suppress increase in energy consumption.SOLUTION: A ferroelectric storage device according to the present invention comprises: a ferroelectric recording medium; a conductive probe that performs writing and reading of information with respect to the ferroelectric recording medium; a probe slider that causes the conductive probe to move in a floating state on a surface of the ferroelectric recording medium; a ferroelectric recording medium driving unit that rotates the ferroelectric recording medium; and a recording reproduction signal processing unit that performs processing on an information writing signal and an information reading signal with the conductive probe. The recording reproduction signal processing unit records information on multiple values including three or more values in the one smallest recording area of the ferroelectric recording medium, and performs reading of the recorded information on the multiple values.SELECTED DRAWING: Figure 8

To provide a ferroelectric recording medium which prevents leakage of electric charge of a ferroelectric layer to the outside, and to provide a ferroelectric storage device.SOLUTION: A ferroelectric recording medium 10 is provided, comprising an electrode layer 12, ferroelectric recording layer 13, and protective layer 14 provided on a substrate 11 in the described order. The substrate 11 has a circular shape in planar view and has an opening 10a in the center thereof. A protective layer 14 is provided in an area other than the opening 10a and its surroundings.SELECTED DRAWING: Figure 2

Provided is a magnetic recording device capable of improving recording density. According to one embodiment, a magnetic recording apparatus 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 perform a first operation. In the first operation, the control unit is configured to supply a recording-time element current to the magnetic element and supply a recording-time coil current to the coil. The absolute value of the coil current during recording is greater than the coil current value. The element current during recording is equal to or less than the first current value.

To provide a ferroelectric storage device that can suppress damage to a probe.SOLUTION: A ferroelectric storage device according to the present invention comprises: a ferroelectric recording medium; a conductive probe that performs writing and reading of information with respect to the ferroelectric recording medium; a probe slider that causes the conductive probe to move in a floating state on a surface of the ferroelectric recording medium; a ferroelectric recording medium driving unit that rotates the ferroelectric recording medium; and a recording reproduction signal processing unit that performs processing on an information writing signal and an information reading signal with the conductive probe. The conductive probe has a substrate composed of a conductive material, a concave part formed in the substrate, and a needle electrode formed into a conical shape in the concave part, and a part of the needle electrode projects from a surface of the conductive material.SELECTED DRAWING: Figure 10

Described are systems and methods for tri-level recording of bits on granular magnetic media, for example using a magnetic writer of a hard disk drive. Tri-level recording of bits involves recording magnetic states that can be read as three distinct levels by a magnetic reader. Tri-level recording within a single recording layer of the granular magnetic storage media can be accomplished by recording bits in a neutral bit state as well as in an up bit state and a down bit state. Neutral bits are recorded by doubling the write frequency so that the write field is reversed over the span of writing a single bit. The resulting neutral bit includes grains whose magnetic states are roughly evenly mixed between up states and down states.

According to one embodiment, a method of adjusting a heat assisted magnetic recording and reproducing device maintains a heat assisted magnetic recording head of the heat assisted magnetic recording and reproducing device in an on-track state, maintains a recording current for data recording below a threshold value, and applies a light source drive current emitting light to a light source.

To provide a data management system that can read information stored in a ferroelectric recording medium at high speed with high recording density and can have high expandability.SOLUTION: A data management system according to the present invention is for storing data on a high-speed communication network, including: at least one external storage device having a data management unit including an internal storage device and a ferroelectric recording medium, in which the data management unit stores data on the high-speed communication network in the external storage device, and stores metadata used for reading the stored data in the internal storage device.SELECTED DRAWING: Figure 30

A high-performance disk device is provided. A plurality of control chips included in the disk device each include a cache control circuit and an arbitration circuit, and control one of a plurality of actuator systems. A first control chip is connected to a buffer memory via the cache control circuit included in the first control chip, and is connected to a second control chip. The second control chip is connected to the first control chip and a third control chip. An arbitration circuit included in the second control chip performs arbitration between data transfer between the third control chip and the first control chip and data transfer between an actuator system controlled by the second control chip among the plurality of actuator systems and the first control chip.

To provide an apparatus and method for enabling rapid transitions during microwave assisted magnetic recording (MAMR) of a storage medium.SOLUTION: In the differential vMode driver for MAMR, the MAMR sensor related circuitry 310 includes a MAMR _ P node 312, a MAMR _ N node 314, a damping element 316, a capacitive element 318, and a resistive element 320. The MAMR _ P and MAMR _ N nodes establish direct connection points between the MAMR sensor driver circuitry and the MAMR sensor. The MAMR _ P node serves as the field inflow terminal through which current ultimately flows from the power supply into the MAMR sensor (resistive element). The MAMR _ N node functions as a field drain terminal, where current drains away from the MAMR sensor and eventually towards ground. These nodes receive a controlled differential voltage produced by the MAMR sensor driver circuitry, which in turn establishes current flow for proper MAMR operation.SELECTED DRAWING: Figure 3

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 perform a first operation. In the first operation, the control unit is configured to supply a recording element current to the magnetic element and a recording coil current to the coil. The absolute value of the recording coil current is greater than or equal to the coil current value. The recording element current is less than or equal to the first current value.