Abstract: A photodetection element includes a magnetic element including a first ferromagnetic layer to which light is applied, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer; a first electrode in contact with a first surface of the magnetic element, the first surface being located on a first ferromagnetic layer side of the magnetic element in a lamination direction; a second electrode in contact with a second surface of the magnetic element, the second surface being opposite to the first surface; and a first high thermal conductivity layer disposed outside of the first ferromagnetic layer and having higher thermal conductivity than the first electrode.

Abstract: An optical sensor includes a wavelength filter configured to transmit light in a specific wavelength range and a magnetic element including a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer. The light passing through the wavelength filter is applied to the magnetic element and the light applied to the magnetic element is detected.

Abstract: A receiving device includes a magnetic element having a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wherein the first ferromagnetic layer is configured to be irradiated with light containing an optical signal with a change of intensity of the light, and wherein the receiving device is configured to receive the optical signal on a basis of an output voltage from the magnetic element.

Abstract: An electrode structure includes: a metal film with an opening formed in a part of the metal film; and a transparent conductive film disposed in the opening, wherein the transparent conductive film is electronically connected to an element and overlaps with the element as viewed in a plan view in a thickness direction of the transparent conductive film.

Abstract: A transceiver device includes: a receiving device including a magnetic element having a first ferromagnetic layer, a second ferromagnetic layer, and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wherein the receiving device is configured to receive an optical signal; a transmission device including a modulated light output element, wherein the transmission device is configured to transmit an optical signal; and a circuit chip including an integrated circuit electrically connected to the magnetic element and the modulated light output element.

Abstract: A photodetection element includes: a first ferromagnetic layer configured to be irradiated with light; a second ferromagnetic layer; and a spacer layer sandwiched between the first ferromagnetic layer and the second ferromagnetic layer, wherein the first ferromagnetic layer includes a first region in contact with the spacer layer and a second region disposed in a position farther from the space layer than the first region, the first region is made of CoFeB alloy, and the second region is a magnetic material containing Fe and Gd as major constituent elements.

Abstract: A positional information sharing system, a positional information sharing method, and a positional information sharing program that is capable of sharing further accurate positions of respective users between each other.

Abstract: An estimation method includes a heating step in which a recording bit, on which a reference signal is recorded, is heated under each of heating conditions having different heating temperatures, the recording bit being at least one recording bit in the magnetic recording medium, and a measurement step in which a signal intensity with respect to the reference signal recorded in the recording bit after heating is measured under each of the heating conditions of the heating step. Based on the signal intensities with respect to the reference signal respectively measured in the measurement step, the distribution width of the Curie temperatures of the plurality of magnetic grains that form the magnetic recording layer is estimated.

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

Abstract: An estimation method includes a heating step in which a recording bit, on which a reference signal is recorded, is heated under each of heating conditions having different heating temperatures, the recording bit being at least one recording bit in the magnetic recording medium, and a measurement step in which a signal intensity with respect to the reference signal recorded in the recording bit after heating is measured under each of the heating conditions of the heating step. Based on the signal intensities with respect to the reference signal respectively measured in the measurement step, the distribution width of the Curie temperatures of the plurality of magnetic grains that form the magnetic recording layer is estimated.

Abstract: A measurement method of a magnetic field gradient of a recording magnetic field generated by a magnetic head in a recording medium includes a step of locally heating the recording medium in a nonmagnetic field state where a magnetic field is not applied to the recording medium at all and measuring a temperature gradient of the recording medium in the nonmagnetic field state, a step of locally heating the recording medium in a recording magnetic field application state where the recording magnetic field is applied to the recording medium and measuring a temperature gradient of the recording medium in the recording magnetic field application state, and a step of calculating a magnetic field gradient of the recording magnetic field based on the temperature gradient of the recording medium in the nonmagnetic field state and the temperature gradient of the recording medium in the recording magnetic field application state.

Abstract: Using a thermally-assisted magnetic recording device, a reference signal is recorded to a magnetic recording medium. After heating each of first and second heating points, where the first and second heating point being positioned respectively at inner and outer sides along a track width direction with respect to a track width center point of a recording bit where the reference signal is recorded, the reproducing signal intensity of the reference signal is measured. Then, obtaining a maximum distance between the first heating point and the second heating point when a reproducing signal intensity measurement value of the reference signal after the magnetic recording medium is heated is approximately zero. Based on the maximum distance, a characterization of the thermally-assisted magnetic recording device is evaluated.

Abstract: A thermally-assisted magnetic recording (TAMR) medium of the present invention includes: a magnetization direction arrangement layer on a substrate; and a magnetic recording layer on the magnetization direction arrangement layer, wherein the magnetization direction arrangement layer is made of at least one selected from a group consisting of Co, Zr, CoZr, CoTaZr, CoFeTaZrCr, CoNbZr, CoNiZr, FeCoZrBCu, NiFe, FeCo, FeAlN, (FeCo)N, FeAlSi, and FeTaC so that a spreading of the heating spot applied from the magnetic head for thermally-assisted recording to the film surface of the magnetic recording medium is suppressed, and that an SN is improved by arranging the magnetization direction of the perpendicularly written recording magnetization to become identical to a perpendicular direction, and realizing the higher recording density.

Abstract: A thermally-assisted magnetic recording head, includes: a pole that generates a writing magnetic field from an end surface that forms a portion of an air bearing surface opposing a magnetic recording medium; a waveguide through which light for exciting a surface plasmon propagates; a plasmon generator that couples to the light in a surface plasmon mode and generates near-field light from a near-field light generating portion on a near-field light generating end surface that forms the portion of the air bearing surface; and magnetic field focusing parts that are able to focus the writing magnetic field generated from the pole and that are disposed on both sides of the pole in a track width direction from a perspective of the air bearing surface side.

Abstract: A giant magneto-resistive effect device (CPP-GMR device) having the CPP (current perpendicular to plane) structure comprising a spacer layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked one upon another with the spacer layer interposed between them, with a sense current applied in a stacking direction, wherein the spacer layer comprises a first nonmagnetic metal layer and a second nonmagnetic metal layer, each made of a nonmagnetic metal material, and a semiconductor oxide layer interposed between the first nonmagnetic metal layer and the second nonmagnetic metal layer, the semiconductor oxide layer that forms a part of the spacer layer contains zinc oxide as its main component wherein the main component zinc oxide contains an additive metal, and the additive metal is less likely to be oxidized than zinc.

Abstract: The invention provides a giant magneto-resistive effect device of the CPP (current perpendicular to plane) structure (CPP-GMR device) comprising a spacer layer, and a first ferromagnetic layer and a second ferromagnetic layer stacked together with said spacer layer sandwiched between them, with a sense current passed in the stacking direction, wherein the first ferromagnetic layer and the second ferromagnetic layer function such that the angle made between the directions of magnetizations of both layers change relatively depending on an external magnetic field, said spacer layer contains a semiconductor oxide layer, and a nitrogen element-interface protective layer is provided at a position where the semiconductor oxide layer forming the whole or a part of said spacer layer contacts an insulating layer.

Abstract: A thermally-assisted magnetic recording method includes first and second steps. The first step applies heat to part of a hard disk medium and forms a moving high-temperature region in a magnetic recording layer of the hard disk medium. The high-temperature region is higher in temperature than a region therearound and has a temperature equal to or higher than the maximum coercivity vanishing temperature of a plurality of magnetic grains contained in the magnetic recording layer. At least one magnetic grain that is adjacent to the rear end of the high-temperature region in the direction of movement of the high-temperature region has a coercivity of a value other than 0. The second step applies a write magnetic field to the hard disk medium such that the write magnetic field applied to the at least one magnetic grain adjacent to the rear end of the high-temperature region is 3 kOe or smaller in magnitude.

Abstract: A thermally-assisted magnetic recording head, includes: a pole that generates a writing magnetic field from an end surface that forms a portion of an air bearing surface opposing a magnetic recording medium; a waveguide through which light for exciting a surface plasmon propagates; a plasmon generator that couples to the light in a surface plasmon mode and generates near-field light from a near-field light generating portion on a near-field light generating end surface that forms the portion of the air bearing surface; and magnetic field focusing parts that are able to focus the writing magnetic field generated from the pole and that are disposed on both sides of the pole in a track width direction from a perspective of the air bearing surface side.

Abstract: A thermally-assisted magnetic recording (TAMR) medium of the present invention includes: a magnetization direction arrangement layer on a substrate; and a magnetic recording layer on the magnetization direction arrangement layer, wherein the magnetization direction arrangement layer is made of at least one selected from a group consisting of Co, Zr, CoZr, CoTaZr, CoFeTaZrCr, CoNbZr, CoNiZr, FeCoZrBCu, NiFe, FeCo, FeAlN, (FeCo)N, FeAlSi, and FeTaC so that a spreading of the heating spot applied from the magnetic head for thermally-assisted recording to the film surface of the magnetic recording medium is suppressed, and that an SN is improved by arranging the magnetization direction of the perpendicularly written recording magnetization to become identical to a perpendicular direction, and realizing the higher recording density.

Abstract: A magnetoresistive effect element is structured in the manner that the antiferromagnetic layer interposed between the upper and lower shields is eliminated and the antiferromagnetic layer is positioned in a so-called shield layer. Therefore, it is realized to solve a pin reversal problem and to allow narrower tracks and narrower read gaps.