Patent application number | Description | Published |
20080205202 | THERMALLY ASSISTED MAGNETIC HEAD, HEAD GIMBAL ASSEMBLY, AND HARD DISK DRIVE - A thermally assisted magnetic head has a medium-facing surface facing a magnetic recording medium; a near-field light generator disposed on a light exit face in the medium-facing surface; a magnetic recording element located adjacent to the near-field light generator; and a light emitting element disposed so that emitted light thereof reaches the near-field light generator; the near-field light generator is comprised of a cusp portion and a base portion; when λin represents a wavelength of the emitted light from the light emitting element immediately before the emitted light reaches the near-field light generator, an intensity of near-field light generated when the material forming the cusp portion is irradiated with the light of the wavelength λin is stronger than an intensity of near-field light generated when the material forming the base portion is irradiated with the light of the wavelength λin. | 08-28-2008 |
20080291583 | Thin film magnetic head comprising metal layer and method of producing the same - A method of producing a thin film magnetic head includes the steps of: forming a pair of openings in a predetermined region of a TMR layer formed on a lower magnetic shield layer; forming a pair of bias-applying layers in the pair of Openings so that an upper surface thereof may be located above an upper surface of the TMR layer; laminating a metal layer that covers the upper surface of a portion located between the pair of bias-applying layers in the TMR layer and the upper surface of the pair of bias-applying layers; forming a resist layer across the upper surface of a portion located above the pair of bias-applying layers in the metal layer and the upper surface of a portion located above the TMR layer in the metal layer; and etching a part of the TMR layer and a part of the pair of bias-applying layers with the resist layer being as a mask. Here, the reflectivity R for the incident light having a wavelength of 248 nm at an interface between the metal layer and the resist layer is set so as to satisfy the condition represented by the following formula (1), and also the magnitude D of a step is set so as to satisfy the condition represented by the following formula (2). | 11-27-2008 |
20090052076 | THERMALLY ASSISTED MAGNETIC HEAD WITH OPTICAL WAVEGUIDE - While an emitting position of light from an optical waveguide and a magnetic pole end part are made closer to each other, high-density writing onto a magnetic recording medium is realized. | 02-26-2009 |
20090168220 | THERMALLY ASSISTED MAGNETIC HEAD AND MANUFACTURING METHOD OF SAME - When first and second near-field light-generating portions are irradiated with laser light or other energy rays, near-field light is generated at the tips of both the near-field light-generating portions. By means of the near-field light thus generated, a magnetic recording medium opposing the medium-opposing surface is heated, and the coercivity of the magnetic recording medium is lowered. Since at least a portion of the main magnetic pole is positioned within the spot region including the region between the first and second near-field light-generating portions, the tips of both the near-field light-generating portions and the main magnetic pole can be brought extremely close together, and high-density recording can be performed. | 07-02-2009 |
20090201600 | THERMALLY ASSISTED MAGNETIC HEAD, HEAD GIMBAL ASSEMBLY, AND HARD DISK APPARATUS - A thermally assisted magnetic head includes a main magnetic pole for writing and a near-field light generator provided near the main magnetic pole, the near-field light generator having a non-magnetic base metal layer, a non-magnetic upper metal layer, an intermediate insulating layer interposed between the base metal layer and the upper metal layer, and the base metal layer having a V-shaped groove and also the upper metal layer having a projection facing the deepest part in the groove of the base metal layer, in a vertical cross-section parallel to a medium facing surface. | 08-13-2009 |
20090262448 | HEAT-ASSISTED MAGNETIC HEAD CONSTITUTED OF SLIDER AND LIGHT SOURCE UNIT, AND MANUFACTURING METHOD OF THE HEAD - Provided is a heat-assisted magnetic recording head constituted of a light source unit and a slider, which can be easily joined to each other with sufficiently high accuracy of joining position. The slider comprises a head part including a waveguide having an incident center on its end. The surface including an emission center of the light source is protruded from a joining surface of the unit substrate. And a step is provided on an end surface of the head part. The protruded portion of a lower surface of the light source has a surface contact with a wall surface of the step. Further, the distance between the wall surface of the step and the incident center of the waveguide is set to be equal to the distance between the emission center of the light source and the protruded portion of the lower surface of the light source. | 10-22-2009 |
20090266789 | MANUFACTURING METHOD OF HEAT-ASSISTED MAGNETIC HEAD CONSTITUTED OF SLIDER AND LIGHT SOURCE UNIT - Provided is a manufacturing method of heat-assisted magnetic recording head, in which a light source unit can be easily joined to a slider with sufficiently high accuracy, under avoiding the excessive mechanical stress. The manufacturing method comprises the steps of: moving relatively the light source unit and the slider, while applying a sufficient voltage between an upper electrode of the light source and an electrode layer provided in the slider; and setting the light source unit and the slider in desired positions in a direction perpendicular to the element-integration surface of the slider substrate. The desired positions are positions where the light source just emits due to a surface contact between: the protruded portion of the lower surface of the light source; and the upper surface of the electrode layer, which is a portion of the wall surface of a step formed on the head part. | 10-29-2009 |
20100061200 | NEAR-FIELD LIGHT GENERATING ELEMENT AND HEAT-ASSISTED MAGNETIC RECORDING HEAD UTILIZING SURFACE PLASMON MODE - Provided is a near-field light generating element capable of avoiding excessive temperature rise, which comprises a waveguide and a near-field light generating layer. The layer comprises: a propagation surface on which surface plasmon excited by the light propagates; and a near-field light generating end at which near-field light is generated. The end is one end of the propagation surface. And a portion of the side surface of the waveguide is opposed to a portion of the propagation surface of the near-field light generating layer with a predetermined spacing so that the light propagating through the waveguide is coupled with the near-field light generating layer in a surface plasmon mode. The near-field light generating layer is preferably tapered toward the near-field light generating end. | 03-11-2010 |
20100073802 | Thermally assisted magnetic head having an asymmetric plasmon antenna and manufacturing method thereof - A thermally assisted magnetic head according to the present invention includes: a medium-facing surface, a main magnetic pole provided on the medium-facing surface, and a plasmon antenna provided on the medium-facing surface in the vicinity of the main magnetic pole, wherein the plasmon antenna is shaped as a triangular flat plate having first, second and third corners, such that the distance from the first corner to the main magnetic pole is shorter than the distance from the second corner to the main magnetic pole and the distance from the third corner to the main magnetic pole, and the interior angle α of the first corner, the interior angle β of the second corner and the interior angle γ of the third corner satisfy relationships α<β, α<γ and β≠γ. | 03-25-2010 |
20100073817 | PLASMON ANTENNA FOR THERMALLY ASSISTED MAGNETIC HEAD - A plasmon antenna of the present invention is used in a thermally assisted magnetic head that includes: a medium-facing surface set, parallel to an XY plane; a magnetic pole for writing, extending toward the medium-facing surface, and a plasmon antenna comprising a pair of small metal bodies irradiated with excitation light for near-field light generation propagating in a Z-axis direction. Respective corners of the small metal bodies are spaced apart opposite each other along a TE mode direction of the excitation light. A distance between the corners gives the shortest distance between the small metal bodies, and a distance from each corner to the leading end of the magnetic pole gives a shortest distance from the small metal bodies to the leading end. | 03-25-2010 |
20100079895 | PLASMON ANTENNA AND HEAT-ASSISTED MAGNETIC RECORDING HEAD - Provided is a plasmon antenna in which a near-field light having a sufficient intensity is generated only in a desired location. The plasmon antenna comprises an end surface on a side where a near-field light is generated; the end surface is flat and has a shape with at least three vertexes or rounded corners; and an end surface of the plasmon antenna which is opposite to the flat end surface and receives light, is inclined with respect to the flat end surface so as to become closer to the flat end surface toward one of the at least three vertexes or rounded corners. When the light-receiving end surface of the plasmon antenna is irradiated with the light, a near-field light having a sufficient intensity can be generated at only the vertex or rounded corner toward which the entire plasmon antenna becomes thinner. | 04-01-2010 |
20100103553 | SURFACE PLASMON ANTENNA WITH PROPAGATION EDGE AND NEAR-FIELD LIGHT GENERATING ELEMENT - Provided is a surface plasmon antenna that can be set so that the emitting position on the end surface of the plasmon antenna where near-field light is emitted is located sufficiently close to the end of a magnetic pole. The surface plasmon antenna comprises an edge having a portion for coupling with a light in a surface plasmon mode. The edge is provided for propagating surface plasmon excited by the light and extends from the portion to a near-field light generating end surface that emits near-field light. The edge for propagating surface plasmon is a very narrow propagation region. Therefore, the near-field light generating end surface, which appears as a polished surface processed through polishing in the manufacturing of the plasmon antenna, can be made a shape with a very small size, and further can be set so that surface plasmon propagates to reach the end surface reliably. | 04-29-2010 |
20100149930 | NEAR-FIELD LIGHT GENERATING ELEMENT COMPRISING SURFACE PLASMON ANTENNA WITH SURFACE OR EDGE OPPOSED TO WAVEGUIDE - Provided is a near-field light generating element in which reduced is the propagation loss of excited surface plasmon that propagates to the near-field light generating end. The element comprises: a waveguide through which light for exciting surface plasmon propagates; and a plasmon antenna comprising a near-field light generating end and a propagation surface or edge. The propagation surface or edge extends to the near-field light generating end, and causes surface plasmon excited by the light to propagate thereon. Further, a portion of the side surface on the near-field light generating end side is opposed to the propagation surface or edge with a predetermined distance so as for the light to be coupled with the plasmon antenna in a surface plasmon mode. In this configuration, surface plasmon can propagates without significantly changing its wavenumber, which leads to a less propagation loss, and to an improved light use efficiency. | 06-17-2010 |
20100172220 | Near-Field Light Generating Element Comprising Surface Plasmon Antenna And Waveguide With Groove - Provided is a near-field light generating element in which as much amount as possible of waveguide light can be coupled with a plasmon antenna. The element comprises a light waveguide and a plasmon antenna comprising a surface or edge for propagating surface plasmon excited by waveguide light, extending to a near-field light generating end. A groove is formed in a waveguide side surface. And at least a portion of the surface or edge is embedded in the groove or located directly above the groove, being opposed to a wall or bottom surface of the groove with a predetermined distance, so as for waveguide light to be coupled with the plasmon antenna in surface plasmon mode. This configuration enables the surface or edge to be located at the position in which the surface or edge can be coupled with more amount of light, thereby to improve the light use efficiency. | 07-08-2010 |
20100195238 | THERMALLY ASSISTED MAGNETIC HEAD HAVING A SEMICONDUCTOR SURFACE-EMITTING LASER - A thermally assisted magnetic head includes: a slider having a medium-facing surface; and a surface-emitting semiconductor laser. The slider has: a slider substrate, on which part of the medium-facing surface is formed; and a magnetic head portion, on which another part of the medium-facing surface is formed, and which has a first surface in contact with a head stacking surface of the slider substrate and a second surface opposite the first surface. The magnetic head portion has: a main magnetic pole that generates a write magnetic field from an end face on the side of the medium-facing surface; an optical waveguide core extending along the first surface and having a light exit surface at the medium-facing surface; and a diffraction grating, which is provided in the optical waveguide core or further towards the second surface than the optical waveguide core, and the refractive index of which varies periodically along the direction in which the optical waveguide core extends. The surface-emitting semiconductor laser is provided opposing the second surface so that emission light from the surface-emitting semiconductor laser is incident onto the diffraction grating, and the diffraction grating causes at least part of emission light from the surface-emitting semiconductor laser to be optically coupled to the optical waveguide core. | 08-05-2010 |
20100202256 | Near-field light generating device including surface plasmon generating element - A near-field light generating device includes: a base having a top surface; a waveguide that allows laser light to propagate therethrough and is disposed above the top surface of the base; and a surface plasmon generating element that is disposed above the top surface of the base so as to adjoin the waveguide in a direction parallel to the top surface of the base. The waveguide has a side surface that faces the surface plasmon generating element. The surface plasmon generating element includes: a coupling part that is opposed to a part of the side surface of the waveguide with spacing therebetween and causes excitation of a surface plasmon by coupling with evanescent light occurring from the part of the side surface; and a near-field light generating part that generates near-field light based on the surface plasmon excited at the coupling part. | 08-12-2010 |
20100238580 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD WITH LIGHT SOURCE ON ELEMENT-INTEGRATION SURFACE - A thermally-assisted magnetic recording head is provided, in which a light source with a sufficient power is disposed in the element-integration surface to improve mass-productivity. The head comprises, in an element-integration surface of a substrate: a light source; a waveguide for propagating light from the light source; and a magnetic pole for generating write field. Further, the edge along optical axis of the light source is set to be parallel with or inclined from the edge on the opposed-to-medium surface side of the element-integration surface. In the head, since the light source is disposed in the element-integration surface, the construction of the optical system can be completed in the stage of a wafer process. This construction can be relatively facilitated and simplified; thus, mass-productivity in the head manufacturing can be improved. Further, a light source with a sufficient power (cavity length) can be disposed in the element-integration surface. | 09-23-2010 |
20100290323 | Near-field light generating device including near-field light generating element with edge part opposed to waveguide - A near-field light generating device includes: a waveguide having a groove that opens in the top surface; a clad layer disposed on the top surface of the waveguide and having an opening that is contiguous to the groove; a near-field light generating element accommodated in the opening; and a buffer layer interposed between the near-field light generating element and each of the waveguide and the clad layer in the groove and the opening. The near-field light generating element includes: first and second side surfaces that decrease in distance from each other toward the groove; an edge part that connects the first and second side surfaces to each other and is opposed to the groove with the buffer layer therebetween; and a near-field light generating part that lies at one end of the edge part and generates near-field light. | 11-18-2010 |
20100329085 | Near-field light generating device including near-field light generating element disposed over waveguide with buffer layer and adhesion layer therebetween - A near-field light generating device includes: a waveguide; a buffer layer disposed on the top surface of the waveguide; an adhesion layer that is formed by incompletely oxidizing a metal layer and disposed on the buffer layer; and a near-field light generating element disposed on the adhesion layer. The adhesion layer has a resistance-area product higher than that of the metal layer unoxidized and lower than that of a layer that is formed by completely oxidizing the metal layer. A layered structure consisting of the buffer layer, the adhesion layer and the near-field light generating element has a peel-test adhesive strength higher than that of a layered structure consisting of the buffer layer and the near-field light generating element. | 12-30-2010 |
20110026377 | Thermally-Assisted Magnetic Recording Head Comprising Light Source with Photonic-Band Layer - A thermally-assisted magnetic recording head is provided, in which a light source having sufficiently high output power for performing thermal-assist is disposed in the element-integration surface of the substrate to achieve improved mass-productivity. The head includes: a light source having a multilayered structure including a photonic-band layer and having a light-emitting surface opposed to the element-integration surface; a diffraction optical element that converges the emitted light; a light-path changer that changes the direction of the converged light; a waveguide that propagates the direction-changed light toward the opposed-to-medium surface; and a magnetic pole that generates write field. The surface-emitting type light source includes a photonic-band layer having a periodic structure in which a light from an active region resonates, and thus emits laser light on a quite different principle from a VCSEL. Therefore, the light source can be disposed in the element-integration surface, even though having sufficiently high output power. | 02-03-2011 |
20110026378 | Heat-assisted magnetic recording head with laser diode - A heat-assisted magnetic recording head includes a slider, and an edge-emitting laser diode fixed to the slider. The slider includes: a substrate; and an MR element, two reproduction wiring layers, a coil, two recording wiring layers, a magnetic pole, a near-field light generating element, and a waveguide that are stacked above the top surface of the substrate. The two reproduction wiring layers supply a sense current to the MR element. The two recording wiring layers supply a coil current to the coil. The laser diode has an emitting end face including an emission part for emitting laser light, and a bottom surface. The laser diode is arranged so that the bottom surface faces the top surface of the slider. As viewed from above, the laser diode does not overlap the two reproduction wiring layers but overlaps at least one of the two recording wiring layers. | 02-03-2011 |
20110090587 | Thermally-Assisted Magnetic Recording Head With Plane-Emission Type Light Source - A thermally-assisted magnetic recording head includes a surface-emitting type light source for emitting substantially collimated beam, a first diffraction optical element for focusing the substantially collimated beam emitted from the surface-emitting type light source, a second diffraction optical element for collimating the light beam focused by the first diffraction optical element, a waveguide integrally formed with the second diffraction optical element and made of the material as that of second diffraction optical element, the light beam collimated by the second diffraction optical element being incident to the waveguide, an optical-path direction conversion element for converting a direction of an optical path of the incident light beam to a propagation direction of the waveguide, the propagation direction being toward an opposed-to-medium surface, and a magnetic pole for generating write field from its end face on the opposed-to-medium surface side. | 04-21-2011 |
20110110202 | Thermally-Assisted Magnetic Recording Head Comprising Near-Field Optical Device with Propagation Edge - There is provided a near-field-light (NFL) generating optical system in which the point where near-field (NF) light is generated can be provided sufficiently close to the end surface of a magnetic pole that generates write field. The optical system comprises: a waveguide through which a light for exciting surface plasmon propagates; and a NF-optical device configured to be coupled with the light in a surface plasmon mode. The NF-optical device comprises: an opposed-to-waveguide surface opposed to the waveguide with a predetermined distance; and a propagation edge provided on the side opposite to the opposed-to-waveguide surface, extending to the NFL-generating end surface of the device, and configured to propagate thereon the surface plasmon excited by the light. In this optical system, the point, where NF-light is generated, of the NFL-generating end surface can be located on the side opposite to the waveguide. | 05-12-2011 |
20110116349 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD COMPRISING NEAR-FIELD OPTICAL DEVICE WITH PROPAGATION EDGE - There is provided a near-field-light (NFL) generating optical system in which the point where near-field (NF) light is generated can be provided sufficiently close to the end surface of a magnetic pole that generates write field. The optical system comprises: a waveguide through which a light for exciting surface plasmon propagates; and a NF-optical device configured to be coupled with the light in a surface plasmon mode. The NF-optical device comprises: a contact-to-waveguide surface having a contact to the waveguide; and a propagation edge provided on the side opposite to the contact-to-waveguide surface, extending to the NFL-generating end surface of the device, and configured to propagate thereon the surface plasmon excited by the light. In this optical system, the point, where NF-light is generated, of the NFL-generating end surface is reliably located on the side opposite to the waveguide. | 05-19-2011 |
20110122737 | Thermally-Assisted Magnetic Recording Head with Light Detector in Element-Integration Surface - A thermally-assisted magnetic recording head is provided, in which the light-source output can be adjusted according to its variation by environmental influences and over time. The head comprises: a light source; a write head element provided in a element-integration surface; an optical system provided in the element-integration surface and configured to guide a light emitted from the light source to the vicinity of one end of the write head element; and a light detector for monitoring the light-source output, provided in the element-integration surface and comprising a light-receiving surface covering an area directly above at least a portion of the optical system. This light detector with such a light-receiving surface can detect a leakage light emitted from the optical system as a monitoring light. Therefore, feedback adjustment of the light-source output can be realized to stabilize the intensity of light for thermal-assist applied to a magnetic recording medium. | 05-26-2011 |
20110157738 | METHOD FOR MANUFACTURING THERMALLY-ASSISTED MAGNETIC RECORDING HEAD BY SEMI-ACTIVE ALIGNMENT - A method for manufacturing a thermally-assisted magnetic recording head is provided, in which joined are: a light source unit that includes a light source having a surface including a light-emission center on the joining surface side of a unit substrate; and a slider that includes an optical system having a light-receiving end surface reaching a back surface opposite to the opposed-to-medium surface. This method utilizes “semi-active alignment” that uses an alignment light, and comprises steps of: causing a light to enter the light source from a surface opposite to the light-emission center; detecting the light that has passed through the light source and is emitted from the light-emission center to align the light-emission center with the light-receiving end surface of the slider; and bonding the light source unit to the slider. This manufacturing method can achieve the alignment with a sufficiently high alignment accuracy in a short processing time. | 06-30-2011 |
20110164479 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD COMPRISING WAVEGUIDE WITH INVERTED-TRAPEZOIDAL SHAPE - Provided is a thermally-assisted magnetic recording head comprising a near-field-light-generating (NFL-generating) optical system with an improved light use efficiency. The head comprises a magnetic pole, a waveguide propagating a light for exciting surface plasmon, and a NF-optical device configured to emit NF-light from its end surface located adjacent to the magnetic pole end surface. The waveguide cross-section, taken by a plane perpendicular to a waveguide edge along elongated direction, has substantially a trapezoidal shape in which a longer side of opposed parallel sides is an edge of the cross-section on the NF-optical device side. This configuration enables a coupled portion of the NF-optical device which is coupled with the light to be placed in the effective distribution range of the light seeping from the waveguide. Consequently, there can be realized a sufficiently strong coupling between the light seeping from the waveguide and the NF-optical device. | 07-07-2011 |
20110205660 | Spot size converter and thermal assist magnetic recording head therewith - A spot size converter according to the present invention is capable of shortening the waveguide length in the spot size converter and of promoting a size reduction of the optical waveguide itself because two cores having a taper portion are combined and those tapering angles are mutually aligned. Furthermore, spot size conversion efficiency is favorable even in a small size. | 08-25-2011 |
20110205661 | Optical waveguide and thermal assist magnetic recording head therewith - An optical waveguide of the present invention is an optical waveguide in order to directly introduce light beams emitted from a light emitting element. In a core that is a waveguide through which light propagates, a concave part is formed that is a depression in a light incident end surface that is one side where light enters. Therefore, an optical waveguide is realized that can obtain a large optical coupling efficiency is possible by the operation of phase alignment in the concave part. | 08-25-2011 |
20110205860 | HEAT-ASSISTED MAGNETIC RECORDING HEAD INCLUDING PLASMON GENERATOR - A plasmon generator has an outer surface including a surface plasmon exciting surface, and has a near-field light generating part located in a medium facing surface. The surface plasmon exciting surface is a flat surface that faces an evanescent light generating surface of a waveguide with a predetermined distance therebetween. The surface plasmon exciting surface includes a width changing portion. The width of the width changing portion in a direction parallel to the medium facing surface and the evanescent light generating surface decreases with decreasing distance to the medium facing surface. A magnetic pole is located at such a position that the plasmon generator is interposed between the magnetic pole and the waveguide. The outer surface of the plasmon generator includes a pole contact surface that is in contact with the magnetic pole. | 08-25-2011 |
20110216634 | HEAT-ASSISTED MAGNETIC RECORDING HEAD INCLUDING PLASMON GENERATOR - A plasmon generator has a near-field light generating part located in a medium facing surface. The plasmon generator has an outer surface including a plasmon exciting surface and a plasmon propagating surface that face toward opposite directions. The plasmon exciting surface is substantially in contact with an evanescent light generating surface of a waveguide's core. The plasmon propagating surface is in contact with a dielectric layer that has a refractive index lower than that of the core. The plasmon exciting surface includes a first width changing portion. The plasmon propagating surface includes a second width changing portion. Each of the first and second width changing portions has a width that decreases with decreasing distance to the medium facing surface, the width being in a direction parallel to the medium facing surface and the evanescent light generating surface. | 09-08-2011 |
20110222184 | OPTICAL WAVEGUIDE AND THERMAL ASSIST MAGNETIC RECORDING HEAD THEREWITH - An optical waveguide, on account of its ability to apply phase resonance of a wavelength and of a first and second triangular plate-like spot size converter members formed of the same material as a core material and being arranged and formed in a substantially symmetrical structure, can promote shortening of the waveguide length and contrive to reduce the size of the optical waveguide itself. Further, an optical waveguide having excellent spot size conversion efficiency can be obtained even in a reduced size. | 09-15-2011 |
20110228419 | HEAT-ASSISTED MAGNETIC RECORDING HEAD INCLUDING PLASMON GENERATOR - A plasmon generator has an outer surface including a propagation edge, and has a near-field light generating part lying at an end of the propagation edge and located in a medium facing surface. The propagation edge faces an evanescent light generating surface of a waveguide's core with a predetermined distance therebetween and extends in a direction perpendicular to the medium facing surface. The propagation edge is arc-shaped in a cross section parallel to the medium facing surface. The plasmon generator includes a shape changing portion in which a radius of curvature of the propagation edge in the cross section parallel to the medium facing surface continuously decreases with decreasing distance to the medium facing surface. | 09-22-2011 |
20110228420 | HEAT-ASSISTED MAGNETIC RECORDING HEAD INCLUDING PLASMON GENERATOR - A plasmon generator has an outer surface including a plasmon exciting part, and has a near-field light generating part located in a medium facing surface. The plasmon exciting part faces an evanescent light generating surface of a waveguide's core with a predetermined distance therebetween. The outer surface of the plasmon generator further includes first and second inclined surfaces that are each connected to the plasmon exciting part. The first and second inclined surfaces increase in distance from each other with increasing distance from the plasmon exciting part. The plasmon generator includes a shape changing portion where the angle of inclination of each of the first and second inclined surfaces with respect to the evanescent light generating surface increases continuously with decreasing distance to the medium facing surface. | 09-22-2011 |
20110235478 | WAVE GUIDE THAT ATTENUATES EVANESCENT LIGHT OF HIGHER ORDER TM MODE - A waveguide has a core through which laser light can propagate in a TM mode, that has a rectangular cross section perpendicular to a propagative direction of the laser light, and through which the laser light can propagate in a fundamental mode in which only one portion exists on the cross section of the core where a light intensity of the laser light becomes maximal, and a higher order mode in which two or more portions exist where the light intensity becomes maximal, a clad surrounding the core, and a light absorbing element in the clad, and wherein a distance between the light absorbing element and the core is shorter than a penetration length of evanescent light in the higher order mode, but is longer than a penetration length of evanescent light in the fundamental mode. | 09-29-2011 |
20110292772 | THERMAL ASSISTED HEAD USING CURVED WAVE GUIDE - A curved waveguide is a curved waveguide that propagates laser light entering from the laser diode as propagating light. The curved waveguide includes a core that is curved in one direction where the propagating light can be propagated and that includes outer surfaces along a propagating direction of the propagating light defined by four surfaces including first and second planar surfaces that curve in respective planar surfaces and that are positioned to face each other, and inside and outside curved surfaces that connect the first and second planar surfaces: an outside metal cladding that is positioned in a direction orthogonal to an oscillation direction of an electric field of the propagating light in a cross section orthogonal to the propagating direction of the propagating light and along the outside curved surface of the core, that is made of gold, silver, copper or aluminum, or that is primarily composed of one component of these materials; and a cladding layer that covers the first and second planar surfaces and the outside metal clad. | 12-01-2011 |
20110310713 | THERMALLY ASSISTED HEAD HAVING REFLECTION MIRROR FOR PROPAGATING LIGHT - A magnetic head includes a magnetic head slider; and a laser diode that is positioned on a surface of a side opposite to a substrate of the magnetic head slider and that generates laser light; the magnetic head slider including: a core through which the laser light emitted from the laser diode propagates as propagating light; a cladding that covers the core and that has a refractive index that is smaller than that of the core; a near field light generating means that generates near field light from the propagating light on an air bearing surface; and a main pole for recording that is disposed adjacent to the near field light generating means and of which an edge part is positioned on the air bearing surface. The core includes a reflection layer and a seed layer, the reflection layer has a refractive index smaller than that of the core, and has a reflection surface on which laser light emitted from the laser diode reflects so as to enter the core as the propagating light, and the seed layer is positioned on a back surface of the reflection surface of the reflection layer and suppresses plasmon generation on the reflection surface. | 12-22-2011 |
20120008470 | MAGNETIC RECORDING HEAD CAPABLE OF MONITORING LIGHT FOR THERMAL ASSIST - Provided is a thermally-assisted magnetic recording head in which a slider including an optical system is joined with a light source unit. The light source unit comprises: a unit substrate including a joining surface joined with the slider and a source-installation surface adjacent to the joining surface; a light source provided in the source-installation surface and emits light for thermal assist; and a photodetector section formed inside the unit substrate, a light-receiving portion of the photodetector section for receiving light emitted from a rear light-emission center being located on the source-installation surface side. The light source unit includes the photodetector section that enables constant monitoring of light output from the light source. Accordingly, feedback adjustment of the light output can be accomplished. Further, since the rear light-emission center and the light-receiving portion can be located sufficiently close to each other, the light output can be monitored with a higher efficiency. | 01-12-2012 |
20120026846 | Thermally-Assisted Magnetic Recording Head Comprising Characteristic Clads - Provided is a thermally-assisted magnetic recording head with improved light density of near-field light (NF-light) with which a medium is irradiated. The head comprises: a magnetic pole; a waveguide for propagating light for exciting surface plasmon; a surface plasmon generator provided between the magnetic pole and the waveguide, coupled with the light in a surface plasmon mode, and emitting NF-light; and a clad portion provided at least between the waveguide and the surface plasmon generator and comprising a transition region in which a refractive index decreases along a direction from the waveguide toward the magnetic pole. The provision of the clad portion including the transition region enables improvement of the light density of NF-light due to the convergence of surface plasmon excited in the surface plasmon generator to predetermined locations, while avoiding the problem of temperature rise due to reduction of the volume of surface plasmon generator. | 02-02-2012 |
20120075967 | THERMALLY ASSISTED MAGNETIC RECORDING HEAD - A thermally assisted magnetic head includes a magnetic pole that generates a writing magnetic field from an air bearing surface (ABS); a waveguide through which light propagates; and a plasmon generator generating near-field light from a near-field light generating end surface by coupling the light thereto in a surface plasmon mode. The magnetic pole includes a convex part protruding in a substantially V-shape along a light propagation direction of the waveguide. The plasmon generator includes a substantially V-shaped part contacting the convex part, and as seen from a side of the ABS, a thickness of the plasmon generator in a direction perpendicular to convex part contacting sides gradually increases from an end in a direction away from the waveguide, the convex part contacting sides being linear sides that form the substantially V-shaped part of the plasmon generator and contacting the convex part. | 03-29-2012 |
20120082016 | OPTICAL WAVEGUIDE AND THERMALLY-ASSISTED MAGNETIC RECORDING HEAD THEREWITH - An optical waveguide of the invention includes a core that is a waveguide through which light propagates; and a cladding that surrounds the core. The core has a plate shape and includes a wide core base part onto which the light is incident, a taper part that is connected to the core base part and of which a width is gradually tapered along a propagation direction, and a narrow front end core part that is connected to the taper part and that extends along the propagation direction. A grating is provided on one of planar surfaces of the wide core base part, the grating is formed by engraving a number of concave grooves having a rectangular cross section on the planar surface along a width direction thereof, the grating is formed to be optically coupled with laser light that is incident perpendicularly onto the grating formation surface, a frequency (grating pitch: pitch of the concave grooves) of the grating is smaller than a wavelength (defined as a wavelength in the cladding) of the perpendicularly incident laser light, and a groove depth H | 04-05-2012 |
20120117791 | METHOD FOR MANUFACTURING A THERMALLY-ASSISTED MAGNETIC HEAD - In a method for manufacturing a thermally-assisted magnetic head that includes a slider and an LD unit, the slider including an air bearing surface (ABS) that faces a recording medium and including a waveguide with a core for light propagation that extends from a light entering surface, which is different from the ABS, to the ABS, the LD unit being attached to the light entering surface of the slider, and the thermally-assisted magnetic head performing magnetic recording while heating the recording medium with near-field light that is excited from linearly polarized laser light, the LD unit is disposed in a position facing the light entering surface of the slider, a photo detector is disposed in a position facing the ABS of the slider, and a polarizer transmitting only light having a polarization component that is orthogonal to a polarization direction of the linearly polarized laser light is disposed between the ABS and the photo detector. An LD of the LD unit is activated, and the linearly polarized laser light is enabled to enter into the core from the light entering surface of the slider. Light radiated from the ABS is enabled to enter into the polarizer, and an alignment of the slider and the LD unit is performed while the photo detector detects light that is transmitted through the polarizer. | 05-17-2012 |
20120120780 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD COMPRISING PLASMON GENERATOR - Provided is a thermally-assisted magnetic recording head in which NF-light with sufficiently high light density can be applied to a medium while a write-field generating point and a near-field light (NF-light) generating point are close to each other. The head comprises a plasmon generator provided between a magnetic pole and a waveguide and configured to be coupled with light propagating through the waveguide in a surface plasmon mode to emit NF-light. The plasmon generator comprises: a plasmon propagating part comprising a propagation edge for propagating surface plasmon excited by the light; and a light penetration suppressing part with an extinction coefficient greater than the plasmon propagating part. The light penetration suppressing part is in surface-contact with a surface portion of the plasmon propagating part excluding the propagation edge, and the magnetic pole is in surface-contact with the light penetration suppressing part. This configuration can avoid significant reduction in light use efficiency of an optical system generating NF-light due to partial absorption of electromagnetic field (light) into the magnetic pole. | 05-17-2012 |
20120120781 | Thermally-Assisted Head Including Surface-Plasmon Resonant Optical System - Provided is a surface plasmon resonating optical system emitting near-field light (NF-light) with a higher light density. The system comprises: a waveguide through which a light for exciting surface plasmon propagates; a plasmon generator that couples with the light in a surface plasmon mode and emits NF-light from its NF-light generating end surface; and a resonator mirror that reflects the excited surface plasmon, provided on the side of the plasmon generator opposite to the NF-light generating end surface. In the system, the excited surface plasmon can be amplified by using a resonator structure while reducing the length of the plasmon generator to reduce absorption of surface plasmon and prevent overheating of the plasmon generator. | 05-17-2012 |
20120127838 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD - A thermally assisted magnetic recording head includes a magnetic recording element part for writing, a main waveguide for assistance for receiving light, and a dummy waveguide component part provided in parallel to the main waveguide. The dummy waveguide component part includes a pair of waveguides having the same shape and dimensions including a first waveguide and a second waveguide that receive light from a back end surface opposite to an air bearing surface and guides the light toward the air bearing surface, and light emitting ends of the first waveguide and the second waveguide facing towards the air bearing surface have no shielding material, and are in a free condition so that the light intensity from the light emitting ends can be measured. | 05-24-2012 |
20120147716 | THERMALLY-ASSISTED MAGNETIC HEAD - A thermally-assisted magnetic head that has an air bearing surface (ABS) facing a recording medium and that performs magnetic recording while heating the recording medium includes: a magnetic recording element that includes a pole of which an edge part is positioned on the ABS and which generates magnetic flux traveling to the recording medium; a waveguide that is configured with a core through which light propagates and a cladding, surrounding a periphery of the core, at least one part of which extends to the ABS; a plasmon generator that faces a part of the core and that extends toward the ABS side; and a bank layer that is positioned between the plasmon generator and the pole, and of which an edge part on the ABS side protrudes relative to the plasmon generator. | 06-14-2012 |
20120176874 | LIGHT SOURCE UNIT INCLUDING A PHOTODETECTOR, AND THERMALLY-ASSISTED MAGNETIC RECORDING HEAD - A light source unit includes a light source and a photodetector. The light source has an emission part for emitting light. The photodetector has a light receiving surface for receiving the light emitted from the emission part, and detects the light. The light source unit further includes a grating made of metal and disposed to extend along the light receiving surface. The grating includes a plurality of line-shaped portions that each extend in a direction intersecting the direction of travel of the light and that are located at positions different from each other along the direction of travel of the light. | 07-12-2012 |
20120213041 | HEAT-ASSISTED MAGNETIC WRITE HEAD, HEAD GIMBALS ASSEMBLY, HEAD ARM ASSEMBLY, AND MAGNETIC DISK DEVICE - A heat-assisted magnetic write head includes: a magnetic pole having an end surface exposed to an air bearing surface; a waveguide extending toward the air bearing surface to propagate light; a plasmon generator provided between the magnetic pole and the waveguide and generating near-field light from the air bearing surface, based on the light propagated through the waveguide; and a clad provided to surround both the waveguide and the plasmon generator collectively, the clad having a refractive index lower than that of the waveguide, and exhibiting a thermal conductivity higher than that of the waveguide. The clad may be provided to collectively surround the magnetic pole, as well. | 08-23-2012 |
20120230168 | HEAT-ASSISTED MAGNETIC WRITE HEAD, HEAD GIMBALS ASSEMBLY, HEAD ARM ASSEMBLY, AND MAGNETIC DISK DEVICE - A heat-assisted magnetic write head includes a magnetic pole having an end surface exposed at an air bearing surface, a waveguide extending toward the air bearing surface to propagate light, a first pair of clads made of a first dielectric material having a refractive index lower than that of the waveguide, and sandwiching the waveguide in a track width direction, and a second pair of clads made of a second dielectric material having a refractive index lower than that of the first dielectric material, and sandwiching the waveguide in a thickness direction orthogonal to the track width direction. Further, the heat-assisted magnetic write head may include, between the magnetic pole and the waveguide, a plasmon generator generating near-field light from the air bearing surface, based on light propagating through the waveguide. | 09-13-2012 |
20120275280 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD, HEAD GIMBAL ASSEMBLY AND MAGNETIC RECORDING DEVICE - A thermally-assisted magnetic recording head includes: a pole that generates a writing magnetic field from an end surface that forms a part of an air bearing surface that opposes a magnetic recording medium; a waveguide that propagates light to excite surface plasmon; and a plasmon generator that is provided between the pole and the waveguide and that generates near-field light from a near-field light generating end surface that forms a part of the air bearing surface by coupling with the light in a surface plasmon mode. The plasmon generator includes a flat plate part and a projection part that projects from the flat plate part to the waveguide side and is provided closer to a trailing side than the pole is. | 11-01-2012 |
20130033972 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD, HEAD GIMBAL ASSEMBLY AND MAGNETIC RECORDING DEVICE - A thermally-assisted magnetic recording head that includes a pole that generates a writing magnetic field, a waveguide through which light propagates, a plasmon generator that surface-evanescent-couples with the light propagating through the waveguide, wherein the plasmon generator includes a portion where a cross-sectional area gradually decreases as going toward a depth side from an air bearing surface when being observed from a cross section parallel to the air bearing surface. The volume of the plasmon generator can be decreased and an exposed area of a front surface on the air bearing surface can be increased. When a thermal expansion from the temperature increase occurs in the plasmon generator, a rate that the plasmon generator projects from the air bearing surface is suppressed to extremely low levels. Accordingly, a chronological degradation of output can be suppressed and thermally-assisted recording having a high and long-term reliability is achieved. | 02-07-2013 |
20130250742 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD, HEAD GIMBALS ASSEMBLY, HEAD ARM ASSEMBLY, MAGNETIC DISK UNIT, AND LIGHT TRANSMISSION UNIT - The thermally-assisted magnetic recording head includes: a laser light source having an emission surface, the emission surface allowing laser light to be emitted therefrom; a waveguide having a core and a cladding, the core allowing the laser light emitted from the laser light source to propagate therethrough, and the cladding surrounding the core; a magnetic pole; and a plasmon generator. Each of the core and the cladding has an end surface facing the emission surface, and the end surface of the cladding suppresses returning of the laser light to the laser light source. | 09-26-2013 |
20130258824 | THERMALLY-ASSISTED MAGNETIC RECORDING HEAD HAVING TEMPERATURE SENSOR EMBEDDED ON DIELECTRIC WAVEGUIDE - A thermal assisted magnetic recording head includes a dielectric waveguide that is configured to propagate propagation light a metal waveguide that is provided facing the dielectric waveguide and that couples to the propagation light propagating through the dielectric waveguide in a surface plasmon mode, thereby generating and propagating surface plasmon, a near-field light generator that is exposed on an air bearing surface facing a magnetic recording medium either at an end part of the metal waveguide or at a position facing the end part of the metal waveguide, and that generates near-field light from the surface plasmon, a magnetic pole for magnetic recording that is exposed on the air bearing surface, and a temperature sensor that is arranged inside the dielectric waveguide. | 10-03-2013 |
20140254333 | POLARIZATION CONVERTER INCLUDING A JAGGED DIAGONAL LINE IN PLANE ORTHOGONAL TO PROPAGATION DIRECTION OF ELECTROMAGNETIC WAVE - A polarization converter of the invention includes a core part that wave-guides an electromagnetic wave and a cladding part that is provided around the core part. The core part includes a conversion part converting a polarization state of the electromagnetic wave. A cross-sectional shape of the conversion part in a plane orthogonal to a propagation direction of the electromagnetic wave is a shape formed by cutting off a portion of a rectangular or square shape along a jagged diagonal line. | 09-11-2014 |
20140269233 | THERMALLY ASSISTED RECORDING HEAD UTILIZING LASER LIGHT WITH LIMITED WAVELENGTH RANGE - A thermally assisted magnetic recording head includes core that propagates laser light as propagation light, a near-field light generator that faces a portion of the core and extends to an air bearing surface (ABS), the near-field light generator coupled to the propagation light propagating through the core so as to generate a surface plasmon, propagating the surface plasmon to an end part facing the ABS, and generating near-field light at the end part to irradiate the near-field light to a magnetic recording medium, a main magnetic pole layer provided in the vicinity of the near-field light generator where an end part is positioned on the ABS, a laser diode that generates laser light of wavelength 890 nm to 1,000 nm and enters the laser light into the core, and a photodiode provided on a silicon substrate measures an intensity of the laser light entering from the laser diode to the core. | 09-18-2014 |