摘要:
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.
摘要:
A thermally-assisted magnetic recording head that allows even steeper magnetization reversal between adjacent magnetic domains of a magnetic recording medium and that satisfies the demands of high SN ratio and high recording density is provided. A thermally-assisted magnetic recording head includes a pole that generates a writing magnetic field, a waveguide through which light for exciting surface plasmon propagates, and a plasmon generator that generates near-field light. The waveguide is arranged on a back side of the pole, the plasmon generator has a plane part and a projection part that is projected from the plane part to the waveguide side and that opposes the pole and the waveguide with a predetermined gap, and a projection part opposing surface that opposes the projection part in the pole is configured so as to be distant from the projection part as approaching toward the back side.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
A near-field light generator includes a waveguide, a plasmon generator, and a metal layer. The waveguide includes a core having an evanescent light generating surface. The plasmon generator includes a base part, and a protruding part that protrudes from the base part toward the evanescent light generating surface. The protruding part has: a front end face located at an end in a direction parallel to the evanescent light generating surface; a band-shaped flat surface facing toward the evanescent light generating surface; and two side surfaces connected to the flat surface. In at least a portion of the protruding part, the distance between the two side surfaces increases with increasing distance from the evanescent light generating surface. The flat surface includes a first portion contiguous with the front end face, and a second portion that is located farther from the front end face than is the first portion. The metal layer has an end face facing the first portion. The evanescent light generating surface faces the second portion.