Abstract: A head transducer includes a thermal sensor comprising a conducting ceramic material having a temperature coefficient of resistance. The thermal sensor can comprise a transparent conducting oxide having a temperature coefficient of resistance. The thermal sensor can be situated proximate a near-field transducer of the heat-assisted magnetic recording head transducer.

Abstract: An apparatus includes a near-field transducer at or near an air bearing surface of the apparatus. A write pole is disposed at or near the air bearing surface and proximate the near-field transducer, respectively. A thermal sensor is disposed at the air bearing surface and within a protrusion region of the air bearing surface defined relative to at least one of the near-field transducer and the write pole. The thermal sensor is configured to produce a signal indicative of a temperature at the protrusion region.

Abstract: Systems and methods and apparatuses for characterizing near field transducer performance at wafer level using asymmetric interference waveguides are provided. One such system includes a light source, an input grating configured to receive light from the light source, a first waveguide arm and a second waveguide arm, each configured to receive the light, a surface plasmon receptor optically coupled to the first waveguide arm and the second waveguide arm and configured to receive light from the first waveguide arm in a first direction and the second waveguide arm in a second direction opposite of the first direction, where the first and the second waveguide arms are configured to induce a preselected phase difference in light arriving at the surface plasmon receptor, and an output grating optically coupled to the surface plasmon receptor, and a light detector coupled to, and configured to detect light from, the first output grating.

Abstract: A device including a magnetic transducer; top and bottom magnetic shields, wherein the top and bottom magnetic shields are adjacent the magnetic transducer on opposite surfaces thereof; a heating element configured to provide heating along a heating path towards the first and second magnetic shields; and a low thermal conductivity structure, wherein at least a portion of the low thermal conductivity structure is positioned along the heating path between the heating element and the magnetic transducer.

Abstract: A heat-assisted magnetic recording system may include, but is not limited to: at least one magnetic recording read/write head; at least one laser diode configured to illuminate at least a portion of at least one magnetic recording medium; at least one laser power level sensor configured to detect a power level of the at least one laser diode; and a controller configured to modify one or more power level settings associated with the at least one laser diode in response to one or more output signals of the at least one laser power level sensor.

Abstract: An apparatus includes a waveguide configured to deliver light to a transducer region. The apparatus also includes a plasmonic transducer that has two metal elements configured as side-by-side plates on a substrate-parallel plane with a gap therebetween. The gap is disposed along the substrate-parallel plane and has an input end disposed proximate the transducer region and an output end. The transducer is configured to provide a surface plasmon-enhanced near-field radiation pattern proximate the output end in response to the light received by the waveguide.

Abstract: A magnetic head includes a reading part, a recording part that is laminated on the reading part in a planer view, a recording part expansion heater, a reading part expansion heater, and a thermal expansion promoting layer that is prepared at a position closer to the reading part than to the recording part and extends to an air bearing surface.

Abstract: An apparatus that includes a write pole, the write pole including a magnetic material; a near field transducer-heat sink (NFT-HS), the NFT-HS including a noble metal; and a power source configured to electrically bias the write pole with respect to a second structure.

Abstract: A microwave-assisted magnetic recording system configured to perform magnetic recording with high density, including a high-frequency magnetic field generation element whose width is narrower than a track width of a main pole. A magnetic field vector from the main pole is perpendicularly incident on a film surface of the high-frequency magnetic field generating unit, by a shield material arranged to have a high magnetic permeability so that the main pole magnetic field is corrected and induced, and a hard bias layer to which a desired static magnetic field is added. Areas having high magnetic field gradients overlap each other by performing an offset of the high-frequency magnetic field generating unit of the magnetic head from the central line of the main pole.

Abstract: A recessed near field transducer (NFT) in a heat-assisted magnetic recording head is manufactured by applying Joule heating to the slider to induce a protrusion of materials of and around the NFT and, while applying the Joule heating, removing the protrusion by lapping the slider. Removing the induced protrusion in this manner causes the NFT to recess into the body of the slider at ambient temperature, whereby during HAMR operation when optical power is being applied to a disk via the NFT, the NFT is substantially flush with the slider air bearing surface.

Abstract: A system including a first circuit, a second circuit, an amplifier, and a summer. The first circuit is configured to (i) select a first portion of a signal, and (ii) generate a first compensation for asymmetry in the first portion of the signal using a first function, where the first function is a modulus function. The second circuit is configured to (i) select a second portion of the signal, and (ii) generate a second compensation for asymmetry in the second portion of the signal using a second function, where the second function is different than the first function. The amplifier amplifies the signal and provides an amplified output. The summer is configured to add (i) the first compensation, (ii) the second compensation, and (iii) the amplified output, where (i) the first circuit, (ii) the second circuit, and (iii) the amplifier are connected in parallel to the summer.

Abstract: A transducer is configured to interact with a magnetic storage medium, a first channel comprises a first sensor and first circuitry configured to adjust a plurality of first channel parameters, and a second channel comprises a second sensor and second circuitry configured to adjust a plurality of second channel parameters. The first and second channel parameters are independently adjustable by the first and second circuitry, respectively. A detector is coupled to the first and second channels, and configured to detect a head-medium interface event.

Abstract: A method and system for providing an energy assisted magnetic recording (EAMR) head are described. The method and system include providing a slider, an EAMR transducer coupled with the slider, and a top layer on the slider. The top layer includes a mirror well therein and has a substantially flat top surface. The method and system further includes providing a laser including a light-emitting surface and providing a mirror optically coupled with the laser. The laser is coupled to the top surface of the top layer external to the mirror well. The mirror has a bottom surface and a reflective surface facing the light-emitting surface of the laser. A portion of the bottom surface of the mirror is affixed to the top surface of the top layer. A portion of the mirror resides in the mirror well.

Abstract: According to one embodiment, a thermally assisted magnetic recording method performs heating at a temperature higher than the ambient temperature of the perpendicular recording medium and lower than a temperature at which a nucleation magnetic field Hn of the recording portion is 0, decreases a coercive force Hc of a recording portion by heating a perpendicular recording medium, and records magnetic information by applying a recording magnetic field from a recording magnetic pole to the recording portion having the decreased coercive force.

Abstract: In a method and an apparatus for inspecting a thermally assisted magnetic recording head element, a specimen is mounted on a table movable in a plane of a scanning probe microscope device, evanescent light is generated from a portion of light emission of evanescent light of the specimen, scattered light of the evanescent light is detected by moving the table in the plane while a cantilever of the scanning probe microscope having a probe is vertically vibrated in the vicinity of a surface of the specimen, and an intensity distribution of the evanescent light emitted from the portion of light emission of evanescent light or a surface profile of the portion of light emission of evanescent light of the specimen is inspected using position information of generation of the evanescent light based on the detected scattered light.

Abstract: A near-field light generating element has a core that propagates light flux from a light incident side to a light emission side while focusing the propagating light flux. A near-field light generating portion in the form of a metal film generates near-field light from the light flux. The core includes a first core, and a second core covering a side surface of the first core, and the core is formed in a polygonal shape when viewed from a Z direction. The metal film is placed on a side surface in the core, and is formed so that a width of an interface between the metal film and the core is narrower than a width of the side surface of the core.

Abstract: An apparatus includes a write pole, a waveguide adjacent to the write pole, the waveguide having a truncated end, and a blocking layer positioned adjacent the truncated end and extending from one side of the waveguide across a portion of an aperture at the truncated end. The waveguide can be a solid immersion mirror or a channel waveguide.

Abstract: Three structures, and processes for manufacturing them, that improve the performance of a TAMR feature in a magnetic write head are disclosed. This improvement is achieved by making the separation between the edge plasmon generator and the plasmon shield less than the separation between the edge plasmon generator and the optical wave-guide.

Abstract: A data media may generally be configured in accordance with various embodiments with contactingly adjacent first and second heatsink layers that are tuned with a common crystallographic orientation and with different thermal conductivities to provide a predetermined thermal gradient. The data media may further be configured with a recording layer formed with the common crystallographic orientation adjacent the first and second heatsink layers.

Abstract: Technologies are described herein for recovering an instable head in a storage device using an internal head heater. An instability in the reader head may be detected, and, in response to detecting the instability, a thermal shock may be applied to the reader head utilizing the head heater to recover the head.

Abstract: In one embodiment, a system includes a medium, a magnetic head having a write element adapted for writing data to the medium, a MAMR element and/or a TAMR element adapted for assisting recording on the medium, the MAMR element having a microwave-generating portion that receives current for operation thereof, the TAMR element having a localized heat-generating portion that receives current for operation thereof, and a read element adapted for reading data from the medium, a device adapted for measuring environmental conditions relating to the TAMR/MAMR elements and the medium, and a controller adapted for controlling operation of the magnetic head and adjusting operating parameters of the system based on the environmental conditions. The environmental conditions include temperature, a reproduced signal of the read element, and/or clearance between the TAMR/MAMR elements and the medium. The operating parameters include the clearance, amount of current injected to the TAMR/MAMR elements, and/or write current.

Abstract: Systems and methods related to writing data to a storage medium. In some cases, a heat assisted loopback circuit is used that includes: a read circuit, a magnetic write circuit, a heat write circuit, and a loopback circuit. The loopback circuit is operable to selectively couple a derivative of a heat output to a read output and to selectively couple a derivative of a write output to the read output.

Abstract: In one embodiment, a method includes forming a conducting material above an insulating film, applying a mask to portions of the conducting material in a shape of a TFC structure, removing exposed portions of the conducting material to form the TFC structure, depositing an insulating film above the TFC structure, and planarizing the insulating film to form a planar upper surface of the insulating film. In another embodiment, a magnetic head includes a TFC structure positioned between insulating films and a magnetic element positioned above the TFC structure, the TFC structure configured for providing localized thermal protrusion of the magnetic head on a media facing surface thereof, wherein an upper surface of an upper of the insulating films is planar, the magnetic element includes at least one of a main magnetic pole and a read sensor, and the TFC structure is configured for providing thermal protrusion of the magnetic element.

Abstract: A method according to one embodiment includes forming a high Ku first oxide magnetic layer above a substrate by sputtering; forming a low Ku second oxide magnetic layer above the first oxide magnetic layer by sputtering; forming an exchange coupling layer of CoCrPt-oxide above the second oxide magnetic layer; and forming a magnetic cap layer above the exchange coupling layer. Additional systems and methods are also presented.

Abstract: According to one embodiment, a magnetic recording medium includes a magnetic recording layer formed on a substrate and including magnetic grains and a grain boundary formed between the magnetic grains, the grain boundary includes a first grain boundary having a first thermal conductivity, and a second grain boundary formed on the first grain boundary and having a second thermal conductivity different from the first thermal conductivity, and at least one of the first and second grain boundaries suppresses thermal conduction.

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

Abstract: A read/write head for reducing flying height in a disk drive apparatus includes a write transducer for storing data on a storage medium, a read transducer for reading data from the storage medium, and read and write heater elements configured so that during read/write operations, heat dissipated in the read heater element is greater than heat dissipated in the write heater element. A control pad in the head receives current supplied to the read and write heater elements during read and write operations. During the write operation, protrusion of the read/write head attributable to the write transducer and the write heater element is greater than a protrusion of the head attributable to the read heater element. During the read operation, protrusion of the read/write head attributable to the read heater element and the read transducer is greater than a protrusion of the head attributable to the write heater element.

Abstract: Approaches for a hard-disk drive (HDD) comprising a head slider comprising a thermoelectric embedded contact sensor. The thermoelectric embedded contact sensor may comprise a first and second conductive lead and a metallic component. The metallic component has a different Seebeck coefficient than the first and second conductive leads. A thermoelectric voltage across the metallic component is used to measure the distance between a head slider and a magnetic-recording disk without supplying an electrical current from a hard-disk drive to either of the first conductive lead or the second conductive lead.

Abstract: Disk drives with preamp rotational parameter control (RPC) using standard digital serial interface lines to the preamp are described. The standard serial interface lines are used to generate a special signal pattern that does not follow the serial communication protocol. The special signal pattern is used to implement RPC when doing so will not interference with other signals, preferably in the read/write recovery gap between the data and the servo field in a standard track format. A value of a selected preamp parameter can be incremented or decremented by one LSB during the read/write gap time in each servo sector as the disk rotates. Embodiments of the invention allow fly-height and write driver parameters to be varied inside of a single disk revolution. Embodiments are described that include two or four parameters in the set, which allows for multiple updates of each parameter per revolution of the disk.

Abstract: A method provides an EAMR transducer. The EAMR transducer is coupled with a laser and has an ABS configured to reside in proximity to a media during use. The EAMR transducer includes an NFT for focusing the energy onto the media. A sacrificial layer is deposited on the NFT and a mask having an aperture provided on the sacrificial layer. A portion of the sacrificial layer exposed by the aperture is removed to form a trench above the NFT. A heat sink is then provided. At least part of the heat sink resides in the trench. The heat sink is thermally coupled to the NFT. Optical material(s) are provided around the heat sink. A write pole configured to write to a region of the media is also provided. The write pole is thermally coupled with the top of the heat sink. Coil(s) for energizing the write pole are also provided.

Abstract: TAR enable write heads may use a plasmonic device (e.g., an optical transducer) which uses electromagnetic energy generated from a laser to heat the magnetic media. However, as the temperature of the plasmonic device rises, the likelihood of stressing the material of the device or other materials of the head near the plasmonic device increases. Accordingly, the write head may include a temperature sensor proximate to the plasmonic device. In one embodiment, the resistance of the temperature sensor may change according to the temperature of the plasmonic device. Based on the measured resistance of the temperature sensor, a sensing circuit may adjust the power of the laser, and thus, prevent the stressing of the materials. Moreover, the thermal coupling between the temperature sensor and a heat sink connected to the plasmonic device may be improved by moving elements associated with the sensing circuit closer to a heat sink.

Abstract: A thermally-assisted magnetic write head includes a waveguide, a magnetic pole, and a plasmon generator interposed between the waveguide and the magnetic pole. The magnetic pole includes a first surface exposed on an air bearing surface, a second surface facing the plasmon generator, and a third surface connecting the first surface and the second surface.

Abstract: The present application discloses a transducer head comprising a read element that reads data from a storage media and an asperity sensor that detects a dimension of an asperity on a surface of the storage media using a temperature change at the asperity sensor. The asperity may be one or both of a void in the surface of the storage media and a protrusion from the surface of the storage media.

Abstract: In accordance with certain embodiments, a magnetic head has a coil, which has a lead coil turn positioned between a yoke and an air-bearing surface. In certain embodiments, a magnetic head has a coil, which has a lead coil turn minimally spaced from a main write pole.

Abstract: In certain embodiments, a head includes a writer portion having coils positioned near a writer, a reader portion separate from the writer portion and a single-layer heating circuit positioned near the writer portion. The heating circuit includes at least two resistive elements. In certain embodiments, a slider includes a single layer heating circuit including at least two heating element resistors.

Abstract: Systems and methods for controlling light phase difference in interferometric waveguides at near field transducers by selectively heating the light source are provided. One such system for controlling light phase at the NFT of an interferometric waveguide includes a laser, a heater configured to heat the laser, a splitter configured to receive light from the laser and to split the light into a first waveguide arm and a second waveguide arm, the first waveguide arm and the second waveguide arm converging at a junction about opposite the splitter, and the NFT proximate the junction and configured to receive the light, where the first waveguide arm is longer than the second waveguide arm by a preselected distance, and where the heater is configured to generate and maintain a preselected phase difference in the light arriving at the NFT via the first waveguide arm and the second waveguide arm.

Abstract: Systems and methods for increasing media absorption efficiency using interferometric waveguides in information storage devices are described. One such system for an interferometric waveguide assembly includes a light source, a first waveguide arm and a second waveguide arm, a splitter configured to receive light from the light source and to split the light into the first waveguide arm and the second waveguide arm, and a near field transducer (NFT) configured to receive the light from the first waveguide arm and the second waveguide arm, where the first waveguide arm and the second waveguide arm converge to form a preselected angle at a junction about opposite the splitter, and where the first waveguide arm and the second waveguide arm are configured to induce a preselected phase difference in the light arriving at the NFT.

Abstract: According to one embodiment, a magnetic head includes a main pole, a write shield pole on a trailing side of the main pole, a recording coil, and a temperature control element unit. The temperature control element unit includes a first electrode on a leading side of the main pole and on both sides of a track of the main pole, a second electrode on the leading side of the main pole and on a track center of the main pole, an N-type semiconductor and a P-type semiconductor connected to the first and second electrodes, and a wiring portion which applies a current via the second electrode, N-type semiconductor, first electrode, P-type semiconductor, and second electrode. The first and second electrodes form a heat absorbing portion and a heat radiating portion.

Abstract: In exemplary embodiments, first and second parameters are obtained for each of different temperatures of the magnetic recording layer. The absolute value of the first parameter for each magnetic grain has a minimum value when the temperature of each magnetic grain reaches a predetermined temperature that increases as the Curie temperature increases, and decreases as the Curie temperature decreases. The second parameter is related to the standard deviation of the coercivity distribution of the magnetic grains divided by the coercivity of the magnetic recording layer. The method calculates a value where the absolute measurement value of the first parameter has a minimum value and the temperature of the magnetic recording layer at which the standard deviation of the coercivity distribution of the magnetic grains divided by the coercivity of the magnetic recording layer has a maximum value.

Abstract: A method for quasi-static testing a magnetic recording head read sensor is described. The method includes applying a first voltage to a heater in the magnetic recording head and measuring an output of the magnetic recording head read sensor while applying the first voltage to the heater and recording the measured output as a first set of measurements. The method further includes applying a second voltage to the heater in the magnetic recording head and measuring the output of the magnetic recording head read sensor while applying the second voltage to the heater and recording the measured output as a second set of measurements. The first and second sets of measurements are then compared.

Abstract: A tape drive is disclosed. The tape drive determines a current tape width and adjusts the length of a tape head to more closely match the current tape width. The tape drive adjusts the length of the tape head by controlling the power to a heating element coupled to the tape head.

Abstract: A method, apparatus, and system are provided for implementing magnetic defect classification using phase modulation for hard disk drives. A magnetic media readback signal of a hard disk drive is processed to identify predefined phase modulation (PM) characteristics to implement magnetic defect classification of magnetic media bump and pit defects.

Abstract: A novel method and apparatus is provided for printing magnetic patterns using heat assisted magnetic recording (HAMR). The apparatus includes an array of probes that is arranged in a predetermined pattern, such as a servo pattern. The array of probes is brought into contact, or near-contact, with a magnetic recording medium that has been bulk erased substantially along an initialization direction. Each probe is energized so as to heat its respective contacted (or near-contacted) region of the recording medium above a threshold temperature. An external magnetic field is applied to the heated regions in a direction that is substantially opposite from the initialization direction. The strength of the external magnetic field is chosen to be greater than the coercivity of the recording medium at the threshold temperature, but less than the coercivity of the recording medium at room temperature. As a result, only magnetizations in the heated regions become aligned with the external field.

Abstract: A DFH (Dynamic Flying Height) type slider ABS design has significantly improved DFH efficiency and back-off efficiency as well as uniform touchdown detectability. This is the result of decoupling the local pressure variations at the read/write head that result from skew angle variations across a disk, from local stiffness due to ABS protrusion caused by heater activation. The decoupling, which allows the heater activation stiffness to be carefully tuned, is a result of the effects of airflow channeled by a wide down-track channel onto a narrow down-track channel formed in an extended finger of the central pad of the slider. Airflow impinges on the finger channel in a manner that eliminates variations in air pressure at the central pad due to variations in skew angle.

Abstract: A magnetic storage apparatus includes a magnetic recording medium, a microwave assisted magnetic recording head at least equipped with a magnetic recording pole that generates a recording magnetic field for writing to the magnetic recording medium and a high-frequency oscillator that generates a high-frequency field, a magnetic reproducing head that reads information from the magnetic recording medium, a signal processing unit that processes a signal written by the magnetic recording head and a signal read by the magnetic reproducing head and a unit that controls clearance between the high-frequency oscillator and the magnetic recording medium. The magnetic storage apparatus has a characteristic that the high-frequency oscillator is not operated except in recording.

Abstract: The present invention enhances reliability by correcting a write error due to unstable oscillation of a spin torque oscillator. In the present invention, a resistance value of a spin torque oscillator is monitored to detect that oscillation becomes unstable during recording. When a measured resistance value is out of a predefined normal range, information for which the recording operation is already performed is rewritten.

Abstract: A reference circuit comprises a first proportional to temperature component providing a first quantity exhibiting a first type of variation as a function of temperature, a first complementary to temperature component providing a second quantity exhibiting a second type of variation as a function of temperature that is complementary to the first type of variation, and curvature correction circuitry. An output of the reference circuit provides a reference signal generated based on a combination of the first and second quantities. The curvature correction circuitry is coupled to the reference circuit output and comprises at least one additional complementary to temperature component. The curvature correction circuitry adjusts the reference signal in a feedback arrangement to compensate for a temperature response bowing effect attributable to combining the first and second quantities. The reference circuit may be implemented in a disk-based storage device for use in fly height control or other control functions.

Abstract: The invention provides a magnetic disk that solves (1) a problem of cross-talk that cannot be solved even by an existing thermally assisted recording method or a discrete method (DTM or the like), (2) a problem of surface flatness, which an existing embedding type DTM or the like has, and (3) a problem of a difference in thermal expansion coefficient between materials when a thermally assisted method is applied to the DTM, and that (4) does not necessitate a special medium structure, and is excellent in a surface flatness and economically and functionally high in realizability. A DTM manufactured by ion implantation is excellent in the surface flatness, and can solve the cross-talk problem by conducting the thermally assisted recording at a temperature between a Curie temperature (Tcn) of a portion where ions are implanted (non-recording region) and a Curie temperature (Tcr) of a portion where ions are not implanted (recording region).

Abstract: A high frequency, AC-modulated heater current is applied to a heater of a magnetic head. A resistance change of a temperature sensor located at a region of proximity to a magnetic media is determined. The resistance change occurs in response to the heater current.

Abstract: A thin film magnetic recording head having a multilayer structure in which plural thin films are laminated and being a perpendicular recording type that applies a magnetic field perpendicularly to a magnetic recording medium and performs recording, includes a main magnetic pole exposed on an air bearing surface facing the magnetic recording medium and guiding a magnetic flux toward the magnetic recording medium, a thin film positioned beneath the main magnetic pole from a perspective of a lamination direction and configuring a sensor or a heater configured to determine a distance from the magnetic recording medium of the thin film magnetic recording head, and a light-absorbing portion positioned between the main magnetic pole and the thin film.