Abstract: According to one embodiment, a data storage device includes a data recording medium, a light source, and following units. The light application unit splits the laser beam from the light source, and applies the first and second light beams to the data recording medium from different directions. The light detection unit detects reflected light beams from the data recording medium. The light deflection unit deflects the reflected light beams to direct the reflected light beams to the light detection unit. The arithmetic unit calculates positional error information based on the detection signal. The drive unit displaces a position and a posture of the data recording medium based on the positional error information.

Abstract: In one embodiment, a magnetic head slider includes a substrate, at least two elements (read element, write element, and/or heater element) positioned adjacent to the substrate, a resistance detection element positioned near the two elements, a pair of conductive terminals in an accessible position and coupled to each of the two elements, a protective film surrounding the two elements and the resistance detection element, a first and a second thin conductive wire extending from the resistance detection clement and terminating at an edge of the protective film, a third thin conductive wire extending from one of the pair of conductive terminals for a first of the two elements and terminating at an edge of the protective film, and a fourth thin conductive wire extending from one of the pair of conductive terminals for a second of the two elements and terminating at an edge of the protective film.

Abstract: A tape drive system according to one embodiment includes a magnetic head. The magnetic head includes first and second beams each having a tape bearing surface, a face, a recess in the tape bearing surface thereof, the faces of the beams facing either towards each other or away from each other; a first chip being positioned in the recess of the first beam; and a second chip being positioned in the recess of the second beam, wherein each chip has circuitry selected from a group consisting of read elements, write elements, and combinations thereof, wherein a tape bearing surface of each chip is generally aligned with the tape bearing surface of the associated beam, and wherein an end of each chip is generally aligned with the face of the associated beam. The system also includes a drive mechanism and a controller.

Abstract: Disclosed is an assembly located in a memory device. The assembly includes: a suspension including a flexure to which a slider is coupled and a load beam disposed at an upper part of the flexure The assembly also includes at least one piezoelectric film coupled to the suspension and configured to control at least one of an angle between the load beam and the flexure in a pitching direction and an angle between the load beam and the flexure in a rolling direction by being extended or contracted when electrical current is applied thereto.

Abstract: There is disclosed a test apparatus for performing testing with a read/write head and method of testing with a test apparatus. The test apparatus includes a head load mechanism for receiving and positioning the read/write head during testing and a multi-channel preamplifier arranged to interface plural channels to a measurement system. A first channel of the multi-channel preamplifier has a connector for connecting to the read/write head. One or more other channels of the multi-channel preamplifier is connected to or has a connector for connecting to another device for interfacing that device to the measurement system.

Abstract: A magnetic head in one embodiment includes a plurality of components separated from each other by insulative portions, one of the components being a substrate; at least one connective element electrically coupling the components together; and a chiplet having at least one of read transducers and write transducers. A magnetic head in another embodiment includes a plurality of components separated from each other by insulative portions; side bars flanking the substrate; and at least one connective element electrically coupling the components together. A magnetic head in another embodiment includes a plurality of components separated from each other by insulative portions; and at least one connective element electrically coupling the components together, wherein the at least one connective element is positioned in at least one of the insulative portions, the at least one connective element having no other function than to electrically connect the components adjacent thereto.

Abstract: In a controller of a tape drive, a command processing unit receives a request to write new data, an offset determination unit determines whether old data is not partially overwritten with new data, and if old data is not partially overwritten with new data, a head position management unit makes a write head offset toward the unoverwritten portion. Then, a channel input/output unit reads pattern data that disables old data from a pattern storage unit and outputs the data to the write head to thereby overwrite the old data with the pattern data. After that, a tape transport management unit rewinds a tape and the head position management unit returns the write head to the original position to overwrite the old data with the new data as usual.

Abstract: In one embodiment, a tunnel magnetoresistance (TMR) head includes a lead layer above a substrate, a seed layer above the lead layer, an antiferromagnetic (AFM) layer above the seed layer, a first ferromagnetic layer above the AFM layer, a second ferromagnetic layer above the first ferromagnetic layer, a coupling layer between the first and second ferromagnetic layers, the coupling layer causing a magnetization of the second ferromagnetic layer to be coupled to a magnetization of the first ferromagnetic layer, a fixed layer above the second ferromagnetic layer, an insertion layer adjacent the fixed layer or in the fixed layer, a barrier layer above the fixed layer, a free layer above the barrier layer, and a cap layer above the free layer. In another embodiment, the insertion layer is from about 0.05 nm to 0.3 nm in thickness and includes Ta, Ti, Hf, and/or Zr, and the free layer includes CoFeB.

Abstract: A magnetic recording/reproducing apparatus 100 includes: a magnetic head 1; a magnetic recording medium 2; a spindle 3 and a spindle motor 4; a suspension arm 5; a voice coil motor 6; and a control unit 7. The control unit 7 has: a motor driver 8; a head amplifier 9; a read/write channel 10; a laser driver 11; and a controller 12. The controller 12 has: a preliminary recording unit 13; a judgment unit 14; an extraction unit 15; a drive condition determining unit 16; and a preliminary recording terminating unit 17. Based on a reproduction signal evaluation value obtained using these units and a predetermined reference value, a drive condition is determined which is suitable for recording onto the magnetic recording medium 2.

Abstract: Approaches for a head slider for use within a hard-disk drive. The head slider comprises an air bearing surface (ABS) and an electromagnetic transducer disposed at an air outflow end of the air bearing surface. The air bearing surface comprises an inner (ID) side rail proximate the inner diameter side and an outer (OD) side rail proximate the outer diameter side. The ID side rail is longer in length than the OD side rail. The physical dimensions of the ID side rail have a geometry that reduces a contact force between the head and the magnetic-recording disk when the head experiences a positive roll static attitude (RSA). The physical dimensions of the OD side rail have a geometry that reduces contact force between the head and the magnetic-recording disk when the head experiences a negative RSA.

Abstract: A method and apparatus for transferring data. First data is transferred in a first direction on a surface of a selected magnetic disk in a plurality of magnetic disks using a first actuator assembly. Second data is transferred in a second direction on the surface of the selected magnetic disk in the plurality of magnetic disks using a second actuator assembly, while the first data is being transferred in the first direction by the first actuator assembly.

Abstract: According to one embodiment, a magnetic head for reading data from a magnetic recording medium by utilizing a magnetic resonance phenomenon includes an auxiliary magnetic pole, a first oscillator, and a second oscillator. The auxiliary magnetic pole is to apply a magnetic field to the magnetic recording medium. The first oscillator is to oscillate at a first frequency and apply, to the magnetic recording medium, a first high-frequency magnetic field corresponding to the first frequency. The second oscillator to oscillate at a second frequency different from the first frequency and apply, to the magnetic recording medium, a second high-frequency magnetic field corresponding to the second frequency.

Abstract: According to one embodiment, a magnetic disk device includes: a magnetic disk having data spiral tracks extending from an outer circumference towards an inner circumference or from an inner circumference towards an outer circumference; a head configured to read data recorded in the data tracks of the magnetic disk that is rotating and to write data to the data tracks; and a controller configured to control the head to follow a predetermined data track in units obtained by subtracting a seek time required for the head to seek the predetermined data track from a rotation period.

Abstract: A magnetic disk device includes: a recording medium provided with a plurality of write tracks; a magnetic write head including a magnetic pole, side shields, and a leading shield, a distance from the magnetic pole to each of the side shields being maintained to be uniform with a gap layer therebetween, and a distance from the magnetic pole to the leading shield being maintained to be uniform with a gap layer therebetween; and a control section rotating the recording medium, and allowing magnetic information to be recorded on the recording medium while allowing the magnetic write head to travel in a direction from an inner write track toward an outer write track or in a direction from the outer write track toward the inner write track, across write tracks in the recording medium. With such a configuration, format efficiency may be improved, and a width of an erase band on a magnetic disk may be minimized.

Abstract: In one general embodiment, a magnetic head comprises an inner module comprising an array of data readers; and first and second outer modules flanking the inner module. The outer modules are identical, each outer module comprising an array of data writers. A number of active data writers in each outer module is less than a number of active data readers in the inner module. For the first outer module, one of the active data writers is aligned with one of the data reader positioned towards a first end of the inner module array in a direction generally parallel to the path of tape travel thereacross. For the second outer module, one of the active data writers is aligned with one of the data readers positioned towards a second end of the inner module array in the direction generally parallel to the path of tape travel thereacross.

Abstract: A magnetoresistive transducer head assembly includes a reader element, a writer element and a high impedance shunt electrically connecting the reader element and the writer element. The high impedance shunt provides a high impedance conductive path for maintaining electrostatic charge equipotential between the reader element and the writer element.

Abstract: A method to position a head module, where the head module comprises at least one servo element and a plurality of data elements, where the servo element and each of the plurality of data elements can detect a servo signal, wherein the method includes moving a sequential information storage medium having a servo band encoded therein across the head module and detecting the servo band using the at least one servo element or any one of the plurality of data elements.

Abstract: A transducer positioning apparatus is provided that supports a read/write head on a data storage machine and biases the head against rotation. The transducer positioning apparatus may comprise a base that includes a linear drive motor and a support frame to which the read/write head is secured. The support frame is reciprocally driven by the linear drive motor relative to the base. A magnetic coupling is provided between the base and the support frame that resists movement of the frame other than the reciprocal movement of the support frame relative to the base. A method is also disclosed for magnetically biasing a movable head of a transducer against rotation.

Abstract: In order to improve a consistent data track during writing to a storage medium, a plurality of read sensors are affixed to a transducer head. In one implementation, the transducer head includes multiple read sensors placed up-track of the write pole. In another implementation, the transducer head includes at least one read sensor placed up-track of the write pole and at least one read sensor placed down-track of the write pole. Each position of the multiple read sensors relative to the write pole may be unique. One or more read signals of selected read sensors are used to determine the read location and therefore the write pole location relative to the storage medium.

Abstract: An assembly according to one embodiment includes a first module and a second module each having multiple transducers, wherein the first module is movable relative to the second module; a tape dimensional stability compensation mechanism for tilting the modules to control a transducer pitch presented to a tape; and an actuator adapted to exert a force on both modules for causing the relative movement of the first module with respect to the second module for aligning the transducers of the first module with the transducers of the second module in a direction of tape travel thereacross.

Abstract: According to one embodiment, a magnetic disc apparatus includes a magnetic head which reads information stored in a magnetic disc, an arm which supports the magnetic head, and a feedback controller which controls a coarse actuator to move the magnetic head above the magnetic disc by driving the arm, a fine actuator to hold a position of the magnetic head, and a feedback path which feeds back a displacement of the actuator to a target value of the coarse actuator. The feedback controller controls decoupling of a double actuator system which adds up the coarse actuator and the fine actuator.

Abstract: According to one embodiment, a magnetic disk drive includes a detector and a servo controller. The detector detects, as actual timestamps, time intervals at which a head reads servo sync marks recorded on a disk at predetermined intervals. The servo controller controls a VCM actuator and a microactuator with feedback control in order to position the head at a target position. The servo controller comprises a feedforward controller configured to compensate for disturbance. The feedforward controller comprises a difference detector and an integrator. The difference detector detects a deviation of the actual timestamps from target timestamps as a timestamp difference. The integrator configured to convert the detected timestamp difference into displacement of the microactuator by integrating the detected timestamp difference.

Abstract: A method and apparatus for bipolar writing of servo marks to perpendicular and non-oriented magnetic recording medium. The method includes applying a varying current to a servo write head to alternately AC-erase and write sets of servo marks to regions of a servo track of a magnetic recording medium proximate to first and second write gaps, each servo mark of the sets of servo marks comprising first and second abutting magnetic domains of opposite magnetization directions, the magnetic recording medium moving with respect to the first and second write gaps in a recording direction, the magnetic recording medium being either (i) a perpendicular magnetic storage medium having magnetic particles with their easy axes oriented perpendicular to a top surface of the perpendicular storage medium or (ii) a non-oriented magnetic storage medium having magnetic particles with their easy axes randomly oriented relative to a top surface of the non-orientated storage medium.

Abstract: According to one embodiment, a disk device rotates a disk information storage medium to record and reproduce information on the information storage medium by use of a head that slides in contact with a lubricant coated on the information storage medium, wherein a sliding speed U, area A and normal force N are set to cause U×A/N to fall within a monotonously increasing region in which a coefficient of friction associated with a frictional force occurring in a contact area of the head that faces the information storage medium monotonously increases as U×A/N increases, where the sliding speed U represents a sliding speed at a sliding time of the head, the area A represents the contact area of the head, and the normal force N represents a normal force applied to the contact area of the head.

Abstract: In one general embodiment, a system includes a module having multiple transducers; and a sizing mechanism for actively applying a force to at least one lateral side of the module for selectively compressing the module, thereby adjusting a pitch between the transducers, wherein the lateral side of the module intersects an axis of the module oriented parallel to the direction of the force. Additional systems and methods are also presented.

Abstract: A method and computer program product for sending a data request from a host bus adapter logic processor to a hard disk drive, setting a standard time out period for receiving a reply from the hard disk drive, sensing vibration in the hard disk drive, sending a vibration alert signal from the hard disk drive to the host bus adapter logic processor in response to the sensed vibration exceeding a predetermined amount of vibration, and, in response to receiving the vibration alert signal from the hard disk drive, the host bus adapter logic processor establishing an extended time out period for receiving the reply. The rotational vibration sensor used by the hard disk drive for repositioning the read/write head may also be used to sense the vibration and form the basis for the vibration alert signal, such as a vibration error code. By extending the time out period during high vibration events, the hard disk drive can ride out the event without being tagged as having failed.

Abstract: A hard disk device includes a disk, a head, and a calculator. The disk includes a plurality of first areas arranged spaced apart in the circumferential direction on a surface of the disk and data-rewritable second areas each located between an adjacent pair of the first areas in the circumferential direction. First servo data is written in the first areas, while second servo data is written in the second areas. The head reads the first servo data and the second servo data written to the surface of the disk. The calculator calculates a displacement amount or a position correction amount of the head based on a result of reading the first servo data and the second servo data by the head.

Abstract: A hard disk drive including a crash stop is disclosed. The crash stop includes a shaft and a resilient member covering a portion of the shaft. In addition, the resilient member includes a right side protrusion and a left side protrusion. The right and left side protrusions are configured to disperse energy from an impact between a head stack assembly and the crash stop.

Abstract: [Problem] A perpendicular magnetic recording medium and a magnetic disk device that are suitable for a shingle recording type are provided. [Solution] The perpendicular magnetic recording medium of the present invention is a perpendicular magnetic recording medium for a shingle recording type having a laminated film including a soft magnetic layer 13 and a main recording layer 16 formed on base 11, the soft magnetic layer 13 having a thickness found from a core width of a magnetic head for recording and reproduction with respect to the perpendicular magnetic recording medium and a track pitch narrower than the core width.

Abstract: In one embodiment a magnetic head includes a sensor thin film adapted for producing a planar Hall voltage, the sensor thin film having a thickness along a down-track direction that is greater than a thickness along a cross-track direction. The down-track direction is in a direction of travel of a magnetic medium relative to the sensor thin film, and the cross-track direction is perpendicular to the down-track direction. In another embodiment, at least one magnetic head as described above is included in a magnetic data storage system, which includes a magnetic medium, a drive mechanism for passing the magnetic medium over the at least one magnetic head, and a controller electrically coupled to the at least one magnetic head for controlling operation of the at least one magnetic head. Other heads and systems are described according to various other embodiments.

Abstract: In one embodiment, a magnetic head includes a main pole having a leading side and a trailing side relative to a downtrack direction, a side gap layer positioned adjacent to the main pole in a crosstrack direction, and a side shield layer positioned adjacent the side gap layer in a crosstrack direction. The downtrack direction is in a direction of medium travel relative to the main pole, the crosstrack direction is perpendicular to the downtrack direction, the side gap layer is characterized by having a groove therein in the downtrack direction having the main pole positioned therein, the side shield is characterized by having a groove formed therein in the downtrack direction having the side gap layer positioned therein, the side gap is non-conformal in shape, and a position of the side shield relative to a position of the main pole is characterized as being self-aligned.

Abstract: According to one embodiment, a magnetic disk drive includes a disk, a first microactuator, a second microactuator and a servo controller. The disk comprises a first surface and a second surface. The first and second microactuators allow first and second heads associated with the first and second surfaces to make micromotion based on first and second operation amounts, respectively. The servo controller provides a third operation amount to the first microactuator as the first operation amount and provides an operation amount obtained by inverting a polarity of a frequency component with a particular frequency contained in the third operation amount, to the second microactuator as the second operation amount, if the third operation amount is generated as an operation amount to be provided to the first microactuator in a particular mode in which the first surface is used as a tracking surface.

Abstract: An information recording device includes a magnetic disk, a recording control module, a detection module, and a rewrite control module. Tracks are defined on the magnetic disk, each track includes servo regions including position information and data regions. The recording control module performs a control so that information is recorded on a first track by a recording method where recording is performed with adjacent tracks overlapped with each other. The detection module detects, based on position information acquired from a first servo region, whether a shift recording is performed so as to be shifted from a reference in a radial direction on the first track. The rewrite control module performs, when the shift recording is detected, a control so that information is re-recorded in a data region between a first servo region and a second servo region that precedes the first servo region.

Abstract: In one embodiment, a perpendicular magnetic recording medium includes a substrate, a soft-magnetic underlayer above the substrate, a seed layer above the soft-magnetic underlayer, a first intermediate layer above the seed layer, a second intermediate layer above the first intermediate layer, a recording layer above the second intermediate layer, and a protective layer above the recording layer. The second intermediate layer includes an Ru alloy having an element selected from a group consisting of: Ti in a range from about 20 at. % to about 50 at. %, Nb in a range from about 20 at. % to about 50 at. %, Al in a range from about 20 at. % to about 40 at. %, Ta in a range from about 30 at. % to about 50 at. %, and Si in a range about 20 at. % to about 40 at. %. Other magnetic media and systems using this media are described according to more embodiments.

Abstract: A method and apparatus for controlling lubrication in hard disk drives. Hard disk drives often include lubrication on the disks to protect the disks from incidental contact with the head slider. Embodiments of the invention include lubrication control recesses on the air bearing surface (ABS) of the head slider. The recesses reduce air stagnation on the ABS and/or store excess lubrication that migrates from the disk to the head slider. By reducing build-up of lubrication and storing excess lubrication, the lubrication control recesses avoid failure that may occur as a result of the lubrication interfering with the ABS or the read/write elements of the head.

Abstract: A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and a controller configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The storage disk is partitioned into at least first and second regions, with the first region having a substantially higher average data transfer rate than the second region and being utilized to store data that is accessed more frequently than data stored in the second region. In one embodiment, the data stored in the first region is not stored in the second region or in any other region of the storage disk, and is randomly distributed across a plurality of sectors of the first region. The first region may comprise one or more outer annular zones of the storage disk and the second region may comprise one or more inner annular zones of the storage disk.

Abstract: A power supply device includes two buck converters, having a coupling inductor Lo composed of two mutually-coupled inductors L1, L2, and a output capacitor Co, wherein of the two buck converters, a first buck converter is operated during a positive half-cycle period of an AC input voltage, and a second buck converter is operated during a negative half-cycle period of the AC input voltage, to obtain a DC output voltage at both ends of the output capacitor Co from the AC input voltage, is provided. Herewith, is provided the power-supply device using the buck converter, which can be reduced in the number of components and produced in a low cost without a diode bridge.

Abstract: Provided are an optical head and an optical information device capable of inhibiting the temperature rise of a photodetector. An optical head (10) includes a semiconductor laser (101) which emits a luminous flux, an objective lens (105) which focuses the luminous flux emitted from the semiconductor laser (101) on the optical disk (21), and a photodetector (120) which detects the luminous flux reflected by the optical disk (21). The photodetector (120) includes a light receiving part (123) which receives the luminous flux reflected by the optical disk (21), a package (125) which covers the light receiving part (123), and a heat transfer adhesion layer (124) disposed between the package (125) and the light receiving part (123). The heat transfer adhesion layer (124) is formed in a region that is on the light receiving part (123) and includes a light path through which the luminous flux reflected by the optical disk (21) passes.

Abstract: A token value is maintained based on an allowable number of low power transitions of a hard disk drive without adversely affecting reliability, compared to an actual number of low power transitions of said hard disk drive. The allowable number of low power transitions increases over the hard disk drive's lifetime. Before the hard disk drive performs a low power transition, the token is evaluated to determine if the hard disk drive is allowed to perform a low power transition. Low power transitions discussed include parking the head and spinning-down the hard disk drive.

Abstract: In one embodiment, a perpendicular magnetic head includes a main magnetic pole, a trailing shield, and a multilayered side/leading shield disposed on a leading side of the main magnetic pole in a down-track direction and on either side of the main magnetic pole in a cross-track direction. The side/leading shield includes an inner layer nearer to the main magnetic pole which surrounds the main magnetic pole on three sides and an outer layer farther from the main magnetic pole than the inner layer which surrounds the main magnetic pole and inner layer on three sides. The inner layer has a saturation magnetization (Ms) that is greater than a Ms of the outer layer, and the trailing shield has a relative permeability of greater than about 50. Other magnetic heads and methods of producing magnetic heads are also presented according to various embodiments.

Abstract: There is provided a motor including a rotating member coupled with a shaft and rotating in connection with the shaft, and a fixing member having the shaft inserted thereinto to support the shaft and including a round part whose outer surface corresponding to the rotating member is formed to be rounded to thereby allow oil to be sealed between the round part and the rotating member.

Abstract: This invention relates to a slider that includes a thermal actuator for controlling the flying height of the slider over a disk in a HDD. The thermal actuator comprises a thermal insulator, a thermal heater and a thermal conductor. The thermal heater is proximate a bottom surface of a slider body on one side of a read/write element. The thermal conductor has a higher thermal coefficient of thermal expansion than a remainder of the slider body and is formed between the first thermal heater and the one side of the read/write element. The first thermal insulator is proximate the bottom surface of the slider body and adjacent to the first thermal heater on an opposing side of the first thermal heater.

Abstract: A magnetic recording apparatus includes: a magnetic disk; a drive device; a magnetic disk control device; a buffer; and a flag management table. The buffer reads data of a specific block unit from a designated read range on the magnetic disk. The flag management table stores a pointer indicating the read location of the buffer for data of each of the block units and a management flag for the pointer. The magnetic disk control device sets the management flag of the pointer corresponding to a given block unit when the data of the given block unit is read to the buffer.

Abstract: According to one embodiment, a magnetic head includes a barrier layer having a crystalline structure, a first magnetic layer above the barrier layer, a magnetic insertion layer above the first magnetic layer, and a second magnetic layer above the magnetic insertion layer, the second magnetic layer having a textured face-centered cubic (fcc) structure. The first magnetic layer comprises a high spin polarization magnetic material having a crystalline structure and a characteristic of crystallization being more similar to the crystalline structure of the barrier layer than a crystalline structure of the second magnetic layer and the magnetic insertion layer comprises a magnetic material having a crystalline structure and a characteristic of crystallization being more similar to the crystalline structure of the second magnetic layer than the crystalline structure of the barrier layer. Additional magnetic head structures and methods of producing magnetic heads are described according to more embodiments.

Abstract: A HDD including a magnetic disk, a magnetic head, an embedded contact sensor embedded in the magnetic head and configured to detect a contact between the magnetic disk and the magnetic head, and TFC embedded in the magnetic head and configured to facilitate in detecting the contact between the magnetic disk and said magnetic head.

Abstract: There is provided a motor including: a rotating member coupled to a shaft and rotating in connection with the shaft; a stationary member having the shaft inserted therein and supporting the shaft; a wall part protruding from a surface of the rotating member and allowing oil to be sealed between the rotating member and the stationary member; and a pumping groove formed in at least one of the wall part and an outer surface of the stationary member corresponding to the wall part and pumping the oil between the shaft and the stationary member.

Abstract: The present invention provides a magnetic recording head and a magnetic recording device that realize information transfer speed exceeding 1 Gbit/s in microwave assisted magnetic recording applied to a magnetic recording device having recording density exceeding 1 Tbit/in2. Concerning a reference layer that supplies spin torque to a high-speed magnetization rotator serving as a microwave field generation source, when an externally applied field to the reference layer is represented as Hext, a magnetic anisotropy field of the reference layer is represented as Hk, and an effective demagnetizing field in a vertical direction of a film surface of the reference layer is represented as Hd-eff, the fixing layer is configured to satisfy conditions Hext?Hk+Hd-eff>0 and Hext+Hk?Hd-eff>0.

Abstract: A magnetic recording head enabling both enhancement of a strength of a magnetic field from a main pole and provision of narrow-track recording to achieve a high recording density in a high-frequency magnetic field-assisted recording method is provided. An oscillator 110 that generates a high-frequency magnetic field is provided on the trailing side of a main pole 120, and viewed from the air bearing surface side, a ratio Pw/Two between a track width Pw of a trailing-side edge portion of the main pole and a track width Two of a leading-side edge portion of the oscillator is no less than 0.85 and no more than 1.25, and the main pole includes a part having a track width larger than Pw between the trailing-side edge portion and a leading-side edge portion of the main pole.

Abstract: In one general embodiment, a magnetic head includes a touch-down pad, comprising at least one shielding element positioned between a leading edge of a main magnetic pole and a trailing edge of a lower return pole; an embedded contact sensor (ECS) in an electrically isolating layer, the ECS positioned near an ABS side of the magnetic head and between the leading edge of the main magnetic pole and the trailing edge of the lower return pole; and a first thermal fly-height control (TFC) element positioned away from the ABS side of the magnetic head. Additional systems and methods are also presented.

Abstract: A track locus drawn on a disk discretely contains repeatable runout (RRO) components which are large in amplitude up to high-frequency band. In order to position a magnetic head along the track locus using filters good at suppressing RRO with resonance characteristics only at an integral multiple of a rotation frequency, many filters are required and thus it takes a long time for all the filters to go into a steady state. After learning until the filers go into a steady state, output values of the filters in a steady state are stored on a disk or in a memory. According to controlling the magnet head using these stored output values, the time required for the filters to go into a steady state becomes unnecessary.