Abstract: Examples of an electromagnetic field detecting element according to the present invention includes a substrate, a pair of electrodes, three insulation layers disposed on the substrate and between the electrodes. The three insulation layers are designed to have two or three different dielectric breakdown strength. At least two ballistic current paths are formed between the electrodes. With this structure, it is possible to perform at a room temperature a highly efficient electromagnetic field detection utilizing Aharonov-Bohm effect or Aharonov-Casher effect.

Abstract: According to one embodiment, a magnetic recording medium includes: a data area on which a plurality of first magnetic dots are arranged at predetermined positions to record information; a servo area on which a plurality of second magnetic dots for specifying the positions of said plurality of first magnetic dots are arranged at predetermined positions; and servo frames configured so that a frequency of said servo frames is 2 N per circumference of said medium having a radius, that said servo frames are radially discontinuous, and that said servo frame and a space-area, on which no servo frames exist, are alternately radially arranged at a cycle W.

Abstract: A magnetic head according to one embodiment includes outer modules each having a media bearing surface and an array of transducers selected from a group consisting of data read transducers and write transducers; and at least one inner module positioned between the outer modules, the inner module having a media bearing surface and an array of transducers selected from a group consisting of data read transducers and write transducers, wherein a configuration of at least one protection feature for the transducers on the outer modules is different than a configuration of at least one protection feature for the transducers on the inner modules.

Abstract: A method for manufacturing a magnetic write head that has a trailing magnetic shield with a tapered write pole trailing edge, a non-magnetic step layer and a Ru bump and an alumina bump formed at the front of the non-magnetic step layer. The process forms a Ru/alumina side wall at the sides of the write pole, such that the Ru side wall is closest to the write pole. The Ru is removed more readily than the alumina during the ion milling that is performed to taper the write pole. This causes the Ru portion of the side wall to taper away from the write pole rather than forming an abrupt step. This tapering prevents dishing of the trailing edge of the write pole for improved write head performance.

Abstract: A magnetic head which includes a core, a coil wound on the core, terminals to which ends of the coil are connected. The magnetic head also includes a substrate on which mounted are a demodulating electronic component for demodulating an analog output signal output from the terminals to create a digital demodulated signal, and an encrypting electronic component for encrypting the demodulated signal to create an encrypted signal. A cable electrically connects the demodulating electronic component and the terminals. A case body stores the core, the coil, the terminals, and the cable. The demodulating electronic component is mounted on one side of the substrate, and the encrypting electronic component is mounted on the other side of the substrate. The substrate is fixed to the case body so that the demodulating electronic component is placed inside the case body while the encrypting electronic component is placed outside the case body.

Abstract: According to one embodiment, a perpendicular magnetic recording head includes a main pole, wherein a thickness in a down-track direction of the main pole increases moving away from an air bearing surface of the magnetic pole, and wherein a center position in a thickness direction of a portion of the main pole which is exposed at the air bearing surface (the ABS portion) is positioned toward a trailing side of the main pole with respect to a center position in a thickness direction of a portion of the magnetic pole having a greatest cross-sectional area and which is set back from the air bearing surface (the set-back portion). Further embodiments of this magnetic recording head, along with systems thereof and methods of producing magnetic recording heads are also described, according to more embodiments.

Abstract: According to one embodiment, a magnetic recording medium includes a substrate, and a magnetic recording layer formed on the substrate and having patterns of protrusions and recesses corresponding to a servo area and a recording area, in which the magnetic recording layer located in each of the recesses in the recording area has a thickness smaller than two thirds of a thickness of the magnetic recording layer corresponding to each of the protrusions, the magnetic recording layer remaining in each of the recesses in the recording area has a thickness of 1 nm or more, and a difference in height on a surface of the magnetic recording medium is 7 nm or less.

Abstract: An example magnetic head includes a recording magnetic pole to generate a recording magnetic field; a spin torque oscillator formed in the vicinity of the recording magnetic pole; and a hard bias film for applying a magnetic field to the spin torque oscillator.

Abstract: A hard disk drive of the invention comprises a housing comprising a base and a cover; at least one disk for storage of data within the housing; an actuator for reading and recording of the data on the at least one disk; and an electrical connector extending through an exiting portion of the base. The exiting portion comprises a recessed portion within the base providing an enlarged opening through which the electrical connector may exit the hard disk drive without direct constraint by the base. The electrical connector also provides electrical contact between electronics external to the housing and one or more component within the hard disk drive.

Abstract: According to one embodiment, a magnetic recording medium includes a substrate, an auxiliary layer formed on the substrate, and at least one perpendicular magnetic recording layer formed on the auxiliary layer. The perpendicular magnetic recording layer includes a magnetic dot pattern. The perpendicular magnetic recording layer is made of an alloy material containing one element selected from iron and cobalt, and one element selected from platinum and palladium. This alloy material has the L10 structure, and is (001)-oriented. The auxiliary layer includes a dot-like first region covered with the magnetic dot pattern, and a second region not covered with the magnetic dot pattern. The first region is made of one metal selected from (100)-oriented nickel and (100)-oriented iron. The second region contains an oxide of the metal used in the first region.

Abstract: A hard disk drive of the invention comprises: a housing comprising a base and a cover; an insert positioned on an interior surface of the base of the housing for stabilization of one or more components within the hard disk drive during operation of the hard disk drive, wherein the insert is relatively stiff as compared to stiffness of the base; and the at least one of the one or more components mounted on the insert. Methods for forming such hard disk drives and hard disk drive rack assemblies comprising the hard disk drives are also disclosed.

Abstract: According to one embodiment, a magnetic recording medium includes a substrate, an auxiliary layer formed on the substrate, and at least one perpendicular magnetic recording layer formed on the auxiliary layer. The perpendicular magnetic recording layer includes a magnetic dot pattern. The perpendicular magnetic recording layer is made of an alloy material containing one element selected from iron and cobalt, and one element selected from platinum and palladium. This alloy material has the L10 structure, and is (001)-oriented. The auxiliary layer includes a dot-like first region covered with the magnetic dot pattern, and a second region not covered with the magnetic dot pattern. The first region is made of a (100)-oriented nickel oxide. The second region contains nickel used in the first region as a main component.

Abstract: An improved hard disk drive of the invention comprises a housing, which comprises a base and a cover. The hard disk drive further internally comprises at least one disk for storage of data within the housing and an actuator for reading and recording of the data on the at least one disk. An electrical connector comprising a flexible circuit extends through an opening in the base and provides electrical contact between electronics external to the housing and one or more component within the hard disk drive. Methods for forming the improved hard disk drives are also disclosed.

Abstract: A magnetic head in one embodiment includes a first array of writers interleaved with readers; a second array of writers interleaved with readers, the writers of the first array being generally aligned with the writers of the second array in a direction of media travel relative thereto, the readers of the first array being generally aligned with the readers of the second array in a direction of media travel relative thereto; and a third array of writers interleaved with readers, the third array being positioned between the first and second arrays, the writers of the third array being generally aligned with the readers of the first and second arrays in a direction of media travel relative thereto, the readers of the third array being generally aligned with the writers of the first and second arrays in a direction of media travel relative thereto. Other embodiments are also presented.

Abstract: A method for manufacturing a magnetic recording medium including at least a non-magnetic substrate, a soft magnetic underlayer, an orientation control layer that controls an orientation of an immediate upper layer, and a perpendicular magnetic layer in which a magnetization easy axis is mainly perpendicularly oriented with respect to the non-magnetic substrate so as to be laminated one another on the non-magnetic substrate. The perpendicular magnetic layer includes two or more magnetic layers, and each layer is subjected to a crystal growth such that each crystal grain composing each magnetic layer forms a columnar crystal continuous in a thickness direction together with the crystal grains composing the orientation control layer. The orientation control layer, formed of a Co—Cr alloy, is formed by the reactive sputtering using a mixture of a sputtering gas and nitrogen.

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: The invention relates to inorganic, intermetallic, inhomogeneous compounds having a magnetic resistance effect and an intrinsic field sensitivity of at least 7% at 1 T at room temperature. The invention further relates to a method for the production and use thereof, particularly as magnetic field sensors or in spin electronics.

Abstract: According to one embodiment, a magnetic head includes a reproducing section. The reproducing section detects a medium magnetic field recorded in a magnetic recording medium. The reproducing section includes a stacked film and a magnetic field application unit. The stacked film includes a first magnetization layer and a second magnetization layer. The first magnetization layer has a perpendicular magnetic anisotropy. A magnetization of the first magnetization layer being is fixed. The second magnetization layer is stacked with the first magnetization layer and oscillates. The magnetic field application unit is stacked with the stacked film and applies a bias magnetic field having a component along the first axis to the stacked film. A resistance of the stacked film changes in accordance with the medium magnetic field when a current not less than a value at which the second magnetization layer oscillates is passed.

Abstract: A spin transfer oscillator (STO) structure is disclosed that includes two assist layers with perpendicular magnetic anisotropy (PMA) to enable a field generation layer (FGL) to achieve an oscillation state at lower current density for MAMR applications. In one embodiment, the STO is formed between a main pole and write shield and the FGL has a synthetic anti-ferromagnetic structure. The STO configuration may be represented by seed layer/spin injection layer (SIL)/spacer/PMA layer 1/FGL/spacer/PMA layer 2/capping layer. The spacer may be Cu for giant magnetoresistive (GMR) devices or a metal oxide for tunneling magnetoresistive (TMR) devices. Alternatively, the FGL is a single ferromagnetic layer and the second PMA assist layer has a synthetic structure including two PMA layers with magnetic moment in opposite directions in a seed layer/SIL/spacer/PMA assist 1/FGL/spacer/PMA assist 2/capping layer configuration. SIL and PMA assist layers are laminates of (CoFe/Ni)x or the like.

Abstract: A patterned perpendicular magnetic recording disk has a Co-alloy recording layer patterned into discrete data islands arranged in concentric tracks and exhibits a narrow switching field distribution (SFD). The disk includes a substrate, a NiTa alloy planarizing layer on the substrate, a nonmagnetic Ru-containing underlayer on the planarizing layer, an oxide-free Co alloy magnetic recording layer, and an ultrathin oxide film between the Ru-containing layer and the Co-alloy magnetic recording layer. The oxide film may be an oxide selected from a Ta-oxide, a Co-oxide and a Ti-oxide, and is ultrathin so that it may be considered a discontinuous film. The planarizing layer and ultrathin oxide film improve the growth homogeneity of the Co-alloy recording layer, so that the patterned disk with data islands shows significantly reduced SFD.

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 method for manufacturing a write head having write pole with a tapered upper surface to improve the channeling of magnetic flux to a pole tip of the write pole. The method includes depositing a first layer of magnetic material over a substrate. A CMP stop layer, image transfer layer and mask structure are deposited over the first magnetic layer, the mask structure being formed with an edge located a desired distance from an air bearing surface plane. An ion milling operation is performed to remove portions of the magnetic layer that are not protected by the mask structure, the ion milling being performed in a manner to form a tapered surface on the first magnetic layer. Then, a second magnetic layer is deposited over the first magnetic layer to form a tapered magnetic write pole.

Abstract: A spin torque oscillation magnetoresistive sensor for measuring a magnetic field. The sensor uses a change in precessional oscillation frequency of a magnetization of a magnetic layer to determine the magnitude of a magnetic field. The sensor can include a magnetic free layer, a magnetic pinned layer and a non-magnetic layer sandwiched therebetween. Circuitry is connected with these layers to induce an electrical current through the layers. Spin polarization of electrons traveling through the device causes a spin torque induced precession of the magnetization of one or more of the layers. The frequency of this oscillation modulates in response to a magnetic field. The modulation of the oscillation frequency can be measured to detect the presence of the magnetic field, and determine its magnitude.

Abstract: In one embodiment, a magnetic head includes a read element, a write element, a write upper shield positioned in a downtrack direction from the write element, a first resistance detecting element positioned on an air bearing surface (ABS) side in a first cross-track direction from the read element, a second resistance detecting element positioned on the ABS side in a second cross-track direction from the write element, a third resistance detecting element positioned on the ABS side in a third cross-track direction from the write upper shield, a protective film positioned near the read and write elements, first, second, and third resistance detecting elements, and the write upper shield, and terminals positioned on an end surface side of the magnetic head, the terminals being coupled to the write element, the read element, the first resistance detecting element, the second resistance detecting element, and the third resistance detecting element.

Abstract: A ferroelectric hard disk device is provided and includes: a ferroelectric media having a bottom electrode and a ferroelectric layer disposed on the bottom electrode; and a head formed above the ferroelectric media, the head being operative to write and reproduce information on the ferroelectric layer.

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: A perpendicular magnetic recording medium of the present invention comprises a non-magnetic substrate, and at least a backing layer, an under layer, an intermediate layer and a perpendicular magnetic recording layer, which are sequentially laminated on the non-magnetic substrate, wherein the backing layer is formed of a soft magnetic film having an amorphous structure, the under layer contains a NiW alloy containing any one or both of Co and Fe, the W content of the NiW alloy is within a range from 3 to 10 atom %, the total of the Co and Fe contents of the NiW alloy is 5 atom % or more and less than 40 atom %, the saturation magnetic flux density Bs of the NiW alloy is 280 emu/cm3 or more, the thickness of the under layer is within a range from 2 to 20 nm, and the intermediate layer contains Ru or a Ru alloy.

Abstract: An aspect of the present invention relates to a glass substrate for a magnetic recording medium, which is comprised of glass with a glass transition temperature of equal to or greater than 600° C., an average coefficient of linear expansion at 100 to 300° C. of equal to or greater than 70×10?7/° C., a Young's modulus of equal to or greater than 81 GPa, a specific modulus of elasticity of equal to or greater than 30 MNm/kg, and a fracture toughness value of equal to or greater than 0.9 MPa·m1/2.

Abstract: According to one embodiment, a recording track has a surface modification layer in the surface region. This surface modification layer has an anisotropic magnetic field Hk reduced from that of a region between adjacent recording tracks.

Abstract: A discrete track-type magnetic recording medium (30) includes a nonmagnetic substrate (1), a magnetic recording track and a servo signal pattern which are provided on at least one side of the nonmagnetic substrate, and a nonmagnetic part (4) consisting of a nonmagnetic alloy containing Si for physically separating the magnetic recording track and the servo signal pattern. A magnetic recording and reproducing device comprising, in combination, the magnetic recording medium (30), a driving part (26) serving to drive the magnetic recording medium in a direction of recording, a magnetic head (27) composed of a recording part and a reproducing part, a device (28) to impart motion to the magnetic head relative to the magnetic recording medium, and a recording and reproducing signal processing device (29) for entering a signal into the magnetic head and reproducing an output signal from the magnetic head.

Abstract: The present invention generally relates to a write head pole laminate structure. The write head pole structure can include multiple multi-layer magnetic structures that are separated by a non-magnetic material that is amorphous or microcrystalline. Each multi-layer magnetic structure includes one or more first magnetic layers that are spaced from one or more second magnetic layers by a non-magnetic layer such that the one or more first magnetic layers are substantially identical to the one or more second magnetic layers. In such a design, the one or more second magnetic layers are antiparallel to the one or more first magnetic layers so that a zero total net magnetic moment is present for the multi-layer magnetic structure when current is removed from the write head pole.

Abstract: The present invention generally relates to a magnetic recording system that utilizes perpendicular exchange spring media and ring heads. The write field of ring heads does not experience a strong loss as compared to pole heads because the pole can be kept long in the direction perpendicular to the recording medium and thus does not result in unfavorable write field scaling.

Abstract: According to one embodiment, a magnetic recording medium includes: a data region including a plurality of first magnetic dots disposed at specific positions for recording data; and a servo region including a plurality of second magnetic dots disposed at specific positions for identifying the position of the first magnetic dots, wherein an address pattern in the servo region is subdivided in the radial direction.

Abstract: According to one embodiment, it is determined whether a STOAR element which performs microwave assistance for a magnetic disk apparatus is made to oscillate properly. When the STOAR element is oscillating when a current bias is applied, the resistance of the element increases. Therefore, in a head IC which outputs the current bias, a voltage applied to the STOAR element is sensed, and it is possible to determine that the STOAR element is oscillating when the voltage is increased to a threshold or more. Conversely, it is possible to determine that the STOAR element is not oscillating when the voltage is less than the threshold. In addition, it is possible to determine that oscillation has diminished, when the resistance decreases after the voltage reaches the threshold or more. Therefore, it is possible to make the STOAR element oscillate normally again, by boosting the STOAR element by a current.

Abstract: A bit-patterned media (BPM) magnetic recording disk has discrete data islands with an exchange-coupled composite (ECC) recording layer (RL) formed of a high-anisotropy chemically-ordered FePt alloy lower layer, a lower-anisotropy Co/X laminate or multilayer (ML) upper layer with perpendicular magnetic anisotropy, wherein X is Pt, Pd or Ni, and an optional nonmagnetic separation layer or coupling layer (CL) between the FePt layer and the ML. The FePt alloy layer is sputter deposited onto a seed layer structure, like a CrRu/Pt bilayer, while the disk substrate is maintained at an elevated temperature to assure the high anisotropy field Hk is achieved. The high-temperature deposition together with the CrRu/Pt seed layer structure provide a very smooth surface for subsequent deposition of the ML (and optional CL). The separate Co/X ML has by itself a very narrow switching field distribution (SFD), so that the SFD of the ECC RL is much narrower than the SFD for the FePt layer alone.

Abstract: According to one embodiment, a magnetic recording head includes a main magnetic pole generating a recording magnetic field in a magnetic recording medium, a return yoke paired with the main magnetic pole and a spin torque oscillator interposed between the main magnetic pole and the return yoke and including a first magnetic layer, a second magnetic layer and a third magnetic layer of Fe4N, the second magnetic layer being interposed between the first magnetic layer and the third magnetic layer, wherein the magnetic recording head is configured to allow a current for oscillation to flow in a direction from the first magnetic layer to the third magnetic layer.

Abstract: According to one embodiment, a magnetic recording medium includes a substrate, a soft magnetic layer, a multilayered underlayer formed on the soft magnetic layer, and a continuous film type magnetic recording layer formed on the multilayered underlayer. The multilayered underlayer includes a first underlayer made of copper and containing crystal grains having a (100)-oriented, face-centered cubic lattice structure, a second underlayer formed on the first underlayer and made of copper and nitrogen, and a third underlayer formed into islands on the second underlayer. The continuous film type magnetic recording layer contains at least one element selected from Fe and Co and at least one element selected from Pt and Pd, has the L10 structure, and mainly contains (001)-oriented magnetic crystal grains.

Abstract: According to one embodiment, a spin torque oscillator includes a field generation layer, a spin injection layer including a first layer and a second layer, and an interlayer interposed between the field generation layer and the spin injection layer, wherein the first layer is interposed between the second layer and the interlayer and includes a (001)-oriented Heuslar magnetic alloy or a (001)-oriented magnetic material having a body-centered cubic lattice structure.

Abstract: According to one embodiment, a perpendicular magnetic recording head includes a shield having a groove and a main magnetic pole positioned in the groove of the shield. The groove includes a bottom side near a leading edge of the shield and inclined sides extending from the bottom side toward a trailing edge of the shield and from an ABS side of the head to a recessed side of the shield opposite the ABS. The shield is coupled to a non-magnetic layer at the recessed side, a cross-sectional area of the groove is less at a position nearer to the substrate than a position farther from the substrate, a cross-sectional area of the groove is less at a position nearer to the ABS side of the shield than a position farther from the ABS side of the shield, and a portion of the sides of the groove have curved surfaces.

Abstract: A method for manufacturing a magnetic write head having a write pole with a tapered, stepped trailing edge. The method includes depositing a magnetic write pole material over a substrate, and then forming a magnetic step structure over the magnetic write pole material. A mask structure is then formed, which includes a multilayer hard mask formed over the magnetic write pole material and the magnetic step structure. An ion milling process is then performed to remove a portion of the write pole material to define a write pole. A non-magnetic material can be deposited and ion milling performed to form non-magnetic side gap layer at the sides of the write pole. A multi-step reactive ion milling process can then be performed to remove the remaining hard mask from over the write pole.

Abstract: A structure for high performance perpendicular magnetic recording media has a substrate with a plurality of sequential layers including an adhesion layer, a first soft underlayer (SUL), a coupling layer, a second SUL, a seed layer, a Ru layer, and an onset layer; at least one oxide layer on the onset layer and having a composition with graded anisotropy to improve overwrite of the media; an exchange coupling layer (ECL) on the at least one oxide layer; a cap layer; a decoupling-controlled layer between the ECL and the cap layer to reduce lateral exchange coupling in the cap layer on the ECL; and a carbon overcoat on the cap layer.

Abstract: A multi-stage sensor is situated on the head transducer and configured to interact with a magnetic recording medium. A first sensor stage of the multi-stage sensor has a temperature coefficient of resistance. A second sensor stage of the multi-stage sensor is coupled to the first sensor and has a temperature coefficient of resistance. The first sensor stage is configured to preferentially sense asperities of the media relative to the second sensor stage, and the second sensor stage configured to preferentially sense proximity to, and contact with, a surface of the media relative to the first sensor stage. The first and second sensor stages may be connected in series or in parallel.

Abstract: A magnetic head includes a pole layer, first and second side shields, and an encasing layer having first to third grooves that accommodate the pole layer and the first and second side shields. A manufacturing method for the magnetic head includes the step of forming the first to third grooves in a nonmagnetic layer by using an etching mask layer having first to third openings. This step includes the steps of forming the first groove by etching the nonmagnetic layer using the first opening, with the second and third openings covered with a first mask; and forming the second and third grooves by etching the nonmagnetic layer using the second and third openings, with the first opening covered with a second mask.

Abstract: A method of manufacturing a magnetic recording medium having a magnetically separated magnetic recording pattern is provided, in which the surface of a magnetic layer is not oxidized or halogenated, the surface is not contaminated with dust, and the manufacturing process is not complex. The method of manufacturing a magnetic recording medium having a magnetically separated magnetic recording pattern includes forming a magnetic layer on a nonmagnetic substrate, forming a mask layer made of carbon to form the magnetic recording pattern on the magnetic layer, forming cobalt carbide as a nonmagnetic material in the magnetic layer by irradiating a region of the magnetic layer not covered by the mask layer with ion beams including carbon hydride ions, and removing the mask layer in this order.

Abstract: A patterned perpendicular magnetic recording disk with discrete data islands of recording layer (RL) material includes a substrate, a patterned exchange bridge layer of magnetic material between the substrate and the islands, and an optional exchange-coupling control layer (CCL) between the exchange bridge layer and the islands. The exchange bridge layer has patterned pedestals below the islands. The exchange bridge layer controls exchange interactions between the RLs in adjacent islands to compensate the dipolar fields between islands, and the pedestals concentrate the flux from the write head. The disk may include a soft underlayer (SUL) of soft magnetically permeable material on the substrate and a nonmagnetic exchange break layer (EBL) on the SUL between the SUL and the exchange bridge layer. In a thermally-assisted recording (TAR) disk a heat sink layer may be located below the exchange bridge layer and the SUL may be optional.

Abstract: A method of manufacturing magnetic recording media with a high areal recording density, in which there write bleeding during magnetic recording is eliminated by reducing insofar as possible the coercive force and remanent magnetization in areas between magnetic tracks, is provided. The method of manufacture can produce magnetic recording media 10, in which a magnetic layer 3 is provided on at least one surface of a nonmagnetic substrate 1, and a magnetically separated magnetic pattern 3a is formed in this magnetic layer 3; by implanting atoms into the magnetic layer 3 with a uniform distribution in the thickness direction of the magnetic layer 3, and partially rendering nonmagnetic the magnetic layer 3, nonmagnetic portions 5 which magnetically separate the magnetic pattern 3a are formed.

Abstract: A hard disk drive has a magnetic media disk comprising a substrate having an axis, and an exchange coupled, bit patterned media on the substrate arranged in a plurality of tracks. Each of the tracks has a pattern of islands extending in an axial direction from the disk. Each island comprises a first layer having a first anisotropy and a first layer radial width, and a second layer on the first layer and having a second anisotropy that is lower than the first anisotropy. The second layer radial width is less than the first layer radial width.

Abstract: A thin film magnetic head includes a medium projection detection mechanism that detects a projection on the surface of a recording medium. The medium projection detection mechanism has a discharging electrode, a capacitor, and an input line and an output line that are connected to the discharging electrode. The discharging electrode is configured to receive a voltage applied through the input line, and the capacitor is configured to store electric charge by the applied voltage. The output line is connected to a projection detection processing system and is connected to the charging electrode and the projection detection processing system to detect the location of the projection that is a detection target by detecting voltage change that is caused by discharging between the discharging electrode and the projection when the projection is detected.

Abstract: A current-perpendicular-to-plane (CPP) tunneling magnetoresistance (TMR) or giant magnetoresistance (GMR) read sensor with ferromagnetic buffer and seed layers is proposed for high-resolution magnetic recording. The ferromagnetic buffer layer is preferably formed of an amorphous Co—X (where X is Hf, Y, Zr, etc.) film. It provides the CPP read sensor with microstructural discontinuity from a ferromagnetic lower shield, thus facilitating the CPP read sensor to grow freely with preferred crystalline textures, and with ferromagnetic continuity to the ferromagnetic lower shield, thus acting as a portion of the ferromagnetic lower shield. The ferromagnetic seed layer is preferably formed of a polycrystalline Ni—X (where X is Pt, Pd, Rh, Ru, etc.) film. It exhibits a face-centered-cubic (fcc) structure and does not exchange-couple with the antiferromagnetic pinning layer.

Abstract: A magnetic recording and reading device, free from coil windings, includes a naturally magnetic material that defines a pair of opposite magnetic poles and defines a magnetic field. A conductor in operable association with an integrated circuit array provided at each of the magnetic poles controls direction and flow of current in the conductors.