Abstract: A data storage device includes a laser diode that heats an area of a disk near the read/write head. To mitigate mode hopping, the laser diode is preheated using the laser diode itself, such as by applying a reverse bias to the laser diode, during an interruption in writing of data to the disk. The laser diode is preheated to a temperature that maintains operation of the laser diode within a middle portion of a preselected gain mode and away from abrupt shifts in gain modes.

Abstract: A data storage device may include a media comprising a magnetic recording layer and a heat-assisted magnetic recording (HAMR) head for writing to the magnetic recording layer, the HAMR head comprising: a waveguide, a main pole comprising a main-pole surface facing the magnetic recording layer, a near-field transducer (NFT) situated between the main pole and the waveguide, and a transparent overcoat. The NFT comprises a main body and a micropillar. The micropillar comprises a micropillar surface facing the magnetic recording layer. A first distance between the micropillar surface and the media is less than a second distance between the main-pole surface and the media. The transparent overcoat is situated on the main-pole surface and the micropillar surface.

Abstract: Various illustrative aspects are directed to a data storage device comprising a disk and a read/write head configured to read data from and write data to the disk. The read/write head comprises a write pole tip and a transducer configured near the write pole tip. One or more processing devices are mounted on or near the read/write head and generate an AC current that is applied to the transducer to cause the transducer to generate a high frequency auxiliary field that is applied to the disk. The one or more processing devices may be an RF source IC mounted on or near a slider on which the read/write head is integrated or mounted.

Abstract: Disclosed is a radiation and magnetic field generating apparatus irradiating photon beam radiation to in-body affected tissue of a subject. The apparatus includes a radiation generating unit that irradiates the photon beam radiation to the subject and induces generation of secondary electrons in an area of the subject where the photon beam radiation is irradiated, a magnetic field generating unit that includes an insertion structure for forming a low-density space and forms a magnetic field in an area in which the secondary electrons are generated, and a synchronization control unit that controls formation of the magnetic field and controls the formation of the magnetic field such that the secondary electrons move while avoiding normal tissue adjacent to the affected tissue.

Abstract: An apparatus includes a substrate. A laser is deposited above the substrate. The laser includes one or more non-self-supporting layers of crystalline material. The laser has a length along a light path in a range of about 40 um to about 350 um. An optical input coupler is configured to receive light from the laser. A waveguide is deposited proximate the optical input coupler. The waveguide is configured to communicate light from the laser via the optical input coupler to a near-field transducer that directs energy resulting from plasmonic excitation to a recording medium.

Abstract: A data storage device may include one or more disks, an actuator arm assembly comprising one or more magnetic recording heads, a laser diode positioned inside a laser diode cavity, and one or more processing devices configured to initiate a write operation, wherein initiating the write operation comprises activating a magnetic recording head corresponding to the laser diode, and applying a forward bias to the laser diode; apply a first reverse bias to the laser diode during at least one intervening event; and transition from applying the first reverse bias to the at least one laser diode to applying the forward bias to the at least one laser diode.

Abstract: A HAMR data storage device may include a magnetic media and a slider comprising: a main pole, a waveguide, and a near-field transducer (NFT) situated between the main pole and the waveguide, wherein an air-bearing surface (ABS) of the slider comprises a transparent overcoat layer situated over the main pole, the waveguide, and the NFT, and wherein the transparent overcoat layer has a particular thickness such that, during an operational phase of the HAMR data storage device, a gap between a media-facing surface of the transparent overcoat layer and the magnetic media is less than about 0.5 nm.

Abstract: Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position a selected head among one or more heads proximate to a corresponding disk surface among the one or more disks, wherein the selected head comprises a magnetic write element and a laser generating component; and one or more processing devices. The one or more processing devices are configured to measure a magnetic saturation responsiveness of the corresponding disk surface to heat-assisted write operations using a range of values of write laser current applied to the laser generating component. The one or more processing devices are further configured to calibrate a nominal write laser current of the selected head for the corresponding disk surface based on the measured magnetic saturation responsiveness of the corresponding disk surface.

Abstract: The present disclosure generally relates to a magnetic recording head comprising a spintronic device for magnetic media, such as a magnetic media drive. The spintronic device includes at least one spin Hall layer as well as at least one buffer layer and at least one interlayer. The buffer layer is positioned proximate a main pole of a write head while the interlayer is positioned proximate a trailing shield of the write head. The spin Hall layer is positioned between the buffer layer and the interlayer. The spintronic element may be disposed at the media facing surface (MFS) or recessed from the MFS. The spintronic device is capable of injecting spin current to the main pole, the trailing shield, or both.

Abstract: Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position a selected head among one or more heads proximate to a corresponding disk surface among the one or more disks; and one or more processing devices. The one or more processing devices are configured to generate a map of laser mode hop effects across the corresponding disk surface, for the selected head. The one or more processing devices are further configured to apply a laser mode hop mitigation in operating the selected head, based on the map of laser mode hop effects.

Abstract: A data storage device may include one or more disks, an actuator arm assembly comprising one or more disk heads, at least one laser diode positioned inside a corresponding laser diode cavity, a preamplifier, and one or more processing devices. The one or more processing devices are configured to: generate a reverse bias; apply, using the preamplifier, the reverse bias to the at least one laser diode to preheat a corresponding laser diode cavity to a target temperature prior to a write operation; control transition of the preamplifier from applying the reverse bias to applying a forward bias to the at least one laser diode; and activate the at least one laser diode to begin the write operation.

Abstract: Various illustrative aspects are directed to a data storage device comprising a disk; a read/write head configured to read data from and write data to the disk; a laser diode configured to heat an area of the disk near the read/write head; and one or more processing devices configured to preheat the laser diode to a target temperature associated with a write operation, wherein the preheating comprises applying (e.g., using a preamplifier) at least one forward bias pulse to the laser diode, wherein a corresponding duration of the at least one forward bias pulse is shorter than a duration of a turn-on delay for the laser diode; and initiate a write operation for writing data to the disk, based at least in part on the preheating.

Abstract: The present disclosure generally relates to a magnetic recording head for a magnetic media drive. The magnetic recording head comprises a main pole, a waveguide disposed adjacent to the main pole, a near field transducer (NFT) coupled between the main pole and the waveguide at a media facing surface (MFS), a thermal shunt disposed on the NFT, the thermal shunt being recessed from the MFS, and a stable material disposed on the NFT at the MFS. In some embodiments, the stable material is wedge-shaped or triangular-shaped. In another embodiment, the stable material comprises a first portion and a second portion, where the first and second portions may each by linear, or where the first portion is triangular-shaped and the second portion is square-shaped. The stable material may be in contact with the thermal shunt, or spaced from the thermal shunt.

Abstract: Various apparatuses, systems, methods, and media are disclosed for heat-assisted magnetic recording (HAMR) that, in some examples, provide a HAMR medium with two soft underlayers (SULs) on opposing sides of a single heatsink layer. For example, a magnetic recording medium is provided that includes a lower SUL on a substrate. The lower SUL is configured and positioned within the medium to provide a first return path for magnetic flux from a magnetic recording head during a write operation. The medium also includes a heatsink layer on the lower SUL and an upper SUL on the heatsink layer. The upper SUL is configured and positioned within the medium to provide a second return path for magnetic flux from the magnetic recording head. A magnetic recording layer is provided on the upper SUL to store information during the write operation. Additional layers or films may be provided as well.

Abstract: Various illustrative aspects are directed to a data storage device, comprising one or more disks; an actuator mechanism configured to position one or more heads proximate to a corresponding disk surface of the one or more disks; and one or more processing devices. The one or more processing devices are configured to generate a determination of magnetic responsiveness to thermal energy of at least one position of the corresponding disk surface in response to an operation of the selected head. The one or more processing devices are further configured to determine and apply a pre-bias current to the thermally energizing component prior to a write operation, with the selected head proximate to the at least one position of the corresponding disk surface, wherein the pre-bias current is based on the determination of magnetic responsiveness to thermal energy of the at least one position of the corresponding disk surface.

Abstract: A heat-assisted magnetic recording (HAMR) head has a slider with a gas-bearing-surface (GBS). The slider supports a near-field transducer (NFT) with an output tip at the GBS and a main magnetic pole with a pole tip at the GBS. The pole tip has a narrow cross-track width that can be substantially the same as the cross-track width of the NFT output tip. A plasmonic layer is located between the main pole and the NFT and has a tip at the GBS between the main pole tip and the NFT output tip. The plasmonic layer may also be located on the cross-track sides of the main pole and the main pole tip.

Abstract: According to one embodiment, a magnetic head includes first and second magnetic poles, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the second magnetic pole and the first magnetic layer, a third magnetic layer provided between the second magnetic pole and the second magnetic layer, a fourth magnetic layer provided between the second magnetic pole and the third magnetic layer, a first non-magnetic layer provided between the first magnetic layer and the first magnetic pole, a second non-magnetic layer provided between the second and first magnetic layers, a third non-magnetic layer provided between the third and second magnetic layers, a fourth non-magnetic layer provided between the fourth magnetic layer and the third magnetic layer, and a fifth non-magnetic layer provided between the second magnetic pole and the fourth magnetic layer.

Abstract: A thermally assisted magnetic head includes a slider having a slider substrate and a magnetic head part, and a light source unit having a laser diode and a sub-mount. The magnetic head part includes a medium-opposite surface, a light source-opposite surface, and a slider-front end surface. The sub-mount includes a joined-end surface and a mount-front end surface, the laser diode includes an electrode surface and an LD-front end surface. The light source unit includes a shift joined structure which the laser diode is joined to a shift area of the joined-end surface, and the light source unit is mounted on the slider substrate so that the electrode surface intersects with a laminated surface of the magnetic head part. The shift area is set in a position which is shifted so that the LD-front end surface is away from the slider-front end surface than the mount-front end surface.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head including a write head which writes data to the magnetic disk, a read head which reads data from the magnetic disk, a first heater which adjusts a flying height of the write head, a second heater which adjusts a flying height of the read head and a controller which controls powers supplied to the first heater and the second heat, and controls a power value of the power supplied to the first heater according to a ratio between an electric resistance value of the first heater and an electric resistance value of the second heater.

Abstract: The present embodiments relate to a heat-assisted magnetic recording (HAMR) write head with a NFT bi-layer structure with a bottom taper, which can be applied to one or both layers of the two layers. A heat-assisted magnetic recording (HAMR) write head can include a main pole including a tip portion configured to interact with a magnetic recording medium at an air-bearing surface (ABS). The HAMR write head can further include a near-field transducer (NFT) that includes a dielectric waveguide, a plasmon generator (PG) layer, and a second layer. The second layer can include a thermo-mechanically stable material disposed adjacent to the PG layer. Further, the PG layer and the second layer can form a taper angle relative to the ABS ranging between 30 and 60 degrees.

Abstract: In accordance with an embodiment, a circuit is configured to vary an intensity of a drive current of a resistive heater element based on the digital control signal. The circuit includes and output circuit configured to control a respective slew rate and an electric energy dissipated in the resistive heater element independently of a resistance value of the resistive heater element.

Abstract: A heat-assisted magnetic recording head includes a laser, a near-field transducer, a primary waveguide, a secondary waveguide, and a photodiode. The laser is configured to emit electromagnetic radiation. The near-field transducer is configured to focus and emit an optical near-field. The primary waveguide configured to receive the electromagnetic radiation and propagate the electromagnetic radiation toward and proximal to the near-field transducer. The secondary waveguide configured to receive a portion of the electromagnetic radiation from the primary waveguide. The photodiode configured to receive the portion of the electromagnetic radiation from the secondary waveguide and emit a signal that represents a magnitude of the electromagnetic radiation that the laser emits.

Abstract: Various apparatuses, systems, methods, and media are disclosed to provide a heat-assisted magnetic recording (HAMR) medium that has a magnetic recording layer on a magnesium oxide-titanium oxide (MTO) underlayer, where the MTO underlayer includes an additive material that chemically bonds with titanium. In some examples, the additive material includes iron-oxide, iron, carbon, or various aluminum oxides. By providing the additive material to the MTO that chemically bonds with the titanium of the MTO, diffusion of titanium from the MTO underlayer into the magnetic recording layer is mitigated to provide an improved recording layer that achieves improved areal densities. In some embodiments, an additional magnesium oxide-nitrogen underlayer is also provided, which may include more of the additive material.

Abstract: A method for writing data to a magnetic data storage medium includes detecting whether the duration, before occurrence of a data transition, of data to be written exceeds a predetermined threshold, and, when the duration, before the occurrence of the data transition, of the data to be written exceeds the predetermined threshold, writing the data by applying an initial pulse and then maintaining a steady-state write current for a defined interval, and when the duration, before the occurrence of the data transition, of the data to be written is at most equal to the predetermined threshold, writing the data by applying the initial pulse without applying a steady-state write current before the data transition. The predetermined threshold may be determined by size of a magnetic bubble formed when writing a single bit to the magnetic data storage medium. A subsequent pulse may be applied following the defined interval.

Abstract: A heat-assisted magnetic recording (HAMR) head has a slider with a gas-bearing-surface (GBS). The slider supports a near-field transducer (NFT) and a main magnetic pole that has a step or recess in the NFT-facing surface near the GBS that contains plasmonic material. A thermal shunt is located between the NFT and the main pole to allow heat to be transferred away from the optical spot generated by the NFT. The NFT-facing surface of the main pole that is recessed from the step away from the GBS is in contact with the thermal shunt, and the thermal shunt is in contact with the plasmonic material in the step in the back region recessed from the GBS, so there is no increase in the spacing between the NFT and a large portion of the main pole.

Abstract: The present disclosure relates to pretreating a magnetic recording head. For a HAMR head, a NFT is present. Current can be applied to the NFT to condition the NFT. The current is applied in one of three ways: slowly ramping up the current from a starting level below a level capable of writing data to the optical laser current over a predetermined period of time, applying the current at a fixed value below the optical laser current for the predetermined period of time, or slowly ramping up the current from a starting level below a level capable of writing data to the optical laser current over the predetermined period of time while also intermittently removing the current. By conditioning the NFT in such a manner, the HAMR head can avoid thermal shock and thermal fatigue and thus increase the lifetime of the magnetic media drive.

Abstract: A heat-assisted magnetic recording head includes a first feature, a second feature, and a bilayer adhesion structure. The first feature includes a first primary metal. The second feature includes an oxide region, and a mixed metal oxide adhesion layer that is adhered to the oxide region and provided on a surface of the second feature. The bilayer adhesion structure includes the mixed metal oxide adhesion layer of the second feature, and a metal adhesion layer. The metal adhesion layer is disposed between and adhered to the first feature and the mixed metal oxide adhesion layer of the second feature. The metal adhesion layer includes a second primary metal that is different than the first primary metal.

Abstract: According to one embodiment, a magnetic recording/reproducing device includes a plurality of magnetic recording medium each including a recording surface, a plurality of assisted magnetic recording heads each provided with the recording surface in order to perform assisted recording, and an assisting amount adjustment part connected to the assisted magnetic recording heads in order to adjust an assisting amount of each assisted magnetic recording head corresponding to a recording capacity of the recording surface.

Abstract: The present disclosure relates to heat-assisted magnetic recording (HAMR) write heads including a waveguide and a main pole having a main pole tip. One or more current paths are provided through the main pole tip. Terminals of the one or more current paths can be coupled to the main pole, a trailing shield, a leading shield, a heat sink layer, a touch pad, a pole diffusion barrier layer, a NTS sensor, or another suitable component of the HAMR write head.

Abstract: Described are heat assisted magnetic read-write heads that include a coupler, a waveguide, a transducer, and appurtenant structures, as well as related methods.

Abstract: A perpendicular magnetoresistive element comprises (counting from the element bottom): a reference layer having magnetic anisotropy in a direction perpendicular to a film surface and having an invariable magnetization direction; a tunnel barrier layer; a crystalline recording layer having magnetic anisotropy in a direction perpendicular to a film surface and having a variable magnetization direction; an oxide buffer layer; and a cap layer, wherein the crystalline recording layer consists of a CoFe alloy that is substantially free of boron and has BCC (body-centered cubic) CoFe grains having epitaxial growth with (100) plane parallel to a film surface.

Abstract: A hard disk drive (HDD) includes a heat-assisted magnetic recording (HAMR) head. The HAMR head includes one or more features comprising a nanoparticle-reinforced plasmonic matrix. The nanoparticle-reinforced plasmonic matrix comprises a plasmonic metal and a plurality of nanoparticles dispersed in the plasmonic metal. The nanoparticles comprise a transparent conductive oxide.

Abstract: A heat-assisted magnetic recording head includes a slider body, a laser, a submount, and a laser heater. The slider body is configured to contain components of the heat-assisted magnetic recording head. The laser is configured to emit electromagnetic radiation. The submount is configured to couple the laser to the slider body. The laser heater is configured to apply heat to the laser. The laser heater disposed on a surface of the slider body.

Abstract: A heat-assisted magnetic recording head comprises a near-field transducer (NFT). The NFT comprises a thermally-stabilized plasmonic alloy, wherein the thermally-stabilized plasmonic alloy comprises a plasmonic metal and at least one alloying metal.

Abstract: A heat-assisted magnetic recording (HAMR) head has a protective multilayer confined to a window of the disk-facing surface of the slider that surrounds the near-field transducer (NFT) end and write pole end. The protective multilayer is made up of a first film of silicon nitride directly on and in contact with the NFT end and the write pole end and a second film of a metal oxide on and in contact with the silicon nitride film. The silicon nitride film is preferably formed by RIBD but is thin enough so that it does not contain any significant amount of other compounds. The metal oxide is preferably silicon dioxide, or alternatively an oxide of hafnium, tantalum, yttrium or zirconium, and together with the silicon nitride film provides a protective multilayer of sufficient thickness to be optically transparent to radiation and resistant to thermal oxidation.

Abstract: The present embodiment relates to a lens driving device comprising: a housing; a bobbin disposed in the housing; a magnet and a dummy member, arranged at the housing; a first coil disposed on the bobbin; and a substrate comprising a second coil facing the magnet, wherein the housing comprises a first and a second side part facing each other and a third and a fourth side part facing each other, the magnet comprises a first magnet unit disposed at the first side part, a second magnet unit disposed at the third side part, and a third magnet unit disposed at the fourth side part, and the dummy member is disposed at the second side part.

Abstract: The present disclosure relates to a recording head that includes a write pole extending to a media-facing surface of the recording head; a near-field transducer extending to a media-facing surface of the recording head; a trailing return pole positioned between the write pole and the trailing edge; and a recessed portion that is recessed relative to the media-facing surface by a distance when no power is applied to the recording head. The trailing return pole is located in the recessed portion. The present disclosure also includes relates methods of making and detecting contact between a recording head and recording medium.

Abstract: A heat-assisted magnetic recording head includes a waveguide and a near-field transducer. The near-field transducer includes a plasmonic disk disposed proximal to the waveguide. The plasmonic disk includes a first plasmonic layer, a second plasmonic layer, and a middle layer. The first plasmonic layer is coupled to the waveguide. The second plasmonic layer is disposed distal to the waveguide relative to the first plasmonic layer. The middle layer is disposed between the first plasmonic layer and the second plasmonic layer.

Abstract: A heat-assisted magnetic recording head includes a near-field transducer including a plasmonic disk and a multilayer near-field emitter. The multilayer near-field emitter is configured to produce a hot spot on a proximal magnetic disk. The multilayer near-field emitter is disposed in a down-track direction relative to and coupled to the plasmonic disk.

Abstract: A heat-assisted magnetic recording head includes a near-field emitter and a middle disk. The near-field emitter includes a peg and an anchor disk. The peg is configured to produce a hot spot on a proximal magnetic disk. The peg is disposed proximal to a media-facing surface of the heat-assisted magnetic recording head. The anchor disk is disposed behind the peg relative to the media-facing surface. The middle disk has a melting temperature of at least 1500 degrees Celsius. The middle disk is disposed in a down-track direction relative to the near-field emitter and is coupled to the anchor disk.

Abstract: The present embodiments relate to a thermally-assisted magnetic recording (TAMR) head. A magnetic assist current can be applied to the TAMR head to assist in reducing timing jitter as the TAMR head interacts with a magnetic recording material. The TAMR head can include a main write pole including a tip portion and configured to direct a magnetic field for interacting with a magnetic recording medium. The TAMR head can include a laser diode to heat the magnetic recording medium and a dynamic fly height (DFH) heating element for dynamically controlling a height of the main write pole. The heating element can be of a parallel bias circuit that directs a direct current (DC) bias current flow along an electrical path from the magnetic yoke element to the tip portion of the main write pole adjacent to an air bearing surface (ABS).

Abstract: Example read transducers, data storage devices, and methods to provide an angled free layer for generating and decoding multi-level read signals are described. The read transducer includes a free layer having a magnetization bias sensitive to an external magnetic field and the direction of the magnetization bias forms an acute angle relative to a surface of the non-volatile storage medium generating the external magnetic field. The read transducer also includes a pinned layer having a fixed magnetization and a direction of the fixed magnetization forms a right angle with the magnetization bias of the free layer. The read transducer targets a readback location on a track boundary between adjacent tracks and generates a read signal indicative of perpendicular and cross-track fields of the adjacent tracks.

Abstract: A recording head has a near-field transducer that extends a first distance away from a media-facing surface. Two subwavelength focusing mirrors are at an end of a waveguide proximate the media-facing surface and extend a second distance away from the media-facing surface that is less than the first distance. The subwavelength mirrors are on opposite crosstrack sides of the near-field transducer and separated from each other by a crosstrack gap. The subwavelength focusing mirrors each include a first material at the media-facing surface and a plasmonic material that covers an edge of the subwavelength focusing mirror that faces the near-field transducer. The first material is more mechanically robust than the plasmonic material.

Abstract: A recording head has a near-field transducer proximate a media-facing surface of the recording head. A waveguide overlaps and delivers light to the near-field transducer. Two subwavelength focusing mirrors are at an end of the waveguide proximate the media-facing surface. The subwavelength mirrors are on opposite crosstrack sides of the near-field transducer and separated from each other by a crosstrack gap. The subwavelength focusing mirrors each include a core having a first edge exposed at the media-facing surface. The core formed of a core material that is resistant to mechanical wear and corrosion, such as a dielectric or robust metal. A liner covers a second edge of the core facing the near-field transducer. The liner includes a plasmonic metal that is different than the core material, such as Au or Al.

Abstract: Aspects of the present disclosure generally relate to a magnetic recording head of a spintronic device, such as a write head of a data storage device, for example a magnetic media drive. In one example, a magnetic recording head includes a main pole, a trailing shield, and a spin torque layer (STL) between the main pole and the trailing shield. The magnetic recording head includes a first layer structure on the main pole, and the first layer structure includes a negative polarization layer. The magnetic recording head also includes a second layer structure disposed on the negative polarization layer and between the negative polarization layer and the STL. The negative polarization layer is an FeCr layer. The second layer structure includes a Cr layer disposed on the FeCr layer, and a Cu layer disposed on the Cr layer and between the Cr layer and the STL.

Abstract: A heat-assisted magnetic recording head includes a near-field transducer and a heat sink. The near-field transducer includes a middle disk and a near-field emitter. The near-field emitter includes a peg and an anchor disk. The peg is configured to produce a hot spot on a proximal magnetic disk. The peg is disposed proximal to a media-facing surface of the heat-assisted magnetic recording head. The anchor disk is disposed behind the peg relative to the media-facing surface. The heat sink includes a core and a liner. The core includes a primary metal, and the liner includes a primary metal. The liner is coupled to the core and is disposed along an outer surface of the core. The middle disk is disposed between and coupled to the liner and the anchor disk. The primary metal of the liner comprises at least one of iridium, rhodium, tantalum, tungsten, or ruthenium.

Abstract: The present disclosure generally relates to a magnetic recording head for a magnetic media drive. The magnetic recording head comprises a near field transducer (NFT), a vertical cavity surface emitting laser (VCSEL) device, and a waveguide structure coupled between the NFT and the VCSEL device. The waveguide structure comprises a plurality of waveguide channels and a multimodal interference (MMI) combiner coupled to the waveguide channels. One or more of a curvature, a path length, and a propagation length of each of the waveguide channels is optimized such that each waveguide channel is controllable, or otherwise phase coherent with adjacent waveguide channels. The VCSEL device is capable of emitting a plurality of lasers through the plurality of waveguide channels, and the plurality of lasers are phase coherent when input into the MMI combiner. The MMI combiner combines a power of the plurality of lasers, which is output to the NFT.

Abstract: The present disclosure relates to pretreating a magnetic recording head for magnetic media drive. For a heat assisted magnetic recording (HAMR) head, a light source provides the necessary heat for the drive to operation. A vertical cavity surface emitting laser (VCSEL) is mounted to a top surface of a slider. A plurality of laser beams are emitted from the bottom surface of the VCSEL and directed to a corresponding number of waveguide structures within the HAMR head. The waveguide structures feed into a multimode interference (MMI) device that then directs the laser into a single waveguide for focusing on a near field transducer (NFT). The VCSEL lasers are phase coherent and have no mode hopping.

Abstract: A heat assisted magnetic recording (HAMR) write head includes a main pole, a waveguide, at least one dielectric matrix layer, and a near-field transducer disposed between the waveguide and the main pole. The near-field transducer is embedded in at least one dielectric matrix layer. The near-field transducer includes an antenna and a thermal shunt. The thermal shunt includes a thermal shunt body portion in direct contact with the antenna, and a metallic shunt diffusion barrier laterally surrounding the thermal shunt body portion and disposed between the thermal shunt body portion and the at least one dielectric matrix layer.

Abstract: According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a control unit, and a setting unit. The magnetic head includes a write element which writes data to the magnetic disk and heater elements which adjust a levitation amount relative to the magnetic disk. The setting unit sets a heater value to be set on the basis of a measurement result of measuring the recording quality of the data written to the magnetic disk. The control unit controls electric power to be supplied to the heater elements on the basis of the heater value to be set to the setting unit.