Abstract: A base multilayer body is made by laminating a seed layer and a buffer layer in respective order. The seed layer is an alloy layer containing tantalum (Ta) and at least one type of other metal, and having an amorphous structure or a microcrystal structure. The buffer layer is an alloy layer having a [001] plane orientation hexagonal close-packed structure and containing at least one type of a group VI metal and at least one type of a group IX metal in the periodic table. With this configuration, a magnetic layer providing a desired magnetic characteristic(s) can be laminated on the thinned base multilayer body.

Abstract: A microwave assisted magnetic head includes a main magnetic pole; a trailing shield; and a spin torque oscillator provided between the main magnetic pole and the trailing shield. The spin torque oscillator has a first end surface configuring a part of an air bearing surface, a second end surface facing the main magnetic pole, and a third end surface facing the first end surface, the first angle ?1 made by the first end surface and the second end surface is smaller than the second angle ?2 formed by the second end surface and the third end surface, and the second angle ?2 is 80 to 100 degrees.

Abstract: A base multilayer body is made by laminating a seed layer and a buffer layer in respective order. The seed layer is an alloy layer containing tantalum (Ta) and at least one type of other metal, and having an amorphous structure or a microcrystal structure. The buffer layer is an alloy layer having a [001] plane orientation hexagonal close-packed structure and containing at least one type of a group VI metal and at least one type of a group IX metal in the periodic table. With this configuration, a magnetic layer providing a desired magnetic characteristic(s) can be laminated on the thinned base multilayer body.

Abstract: A microwave assisted magnetic head includes a main magnetic pole; a trailing shield; and a spin torque oscillator provided between the main magnetic pole and the trailing shield. The spin torque oscillator has a first end surface configuring a part of an air bearing surface, a second end surface facing the main magnetic pole, and a third end surface facing the first end surface, the first angle ?1 made by the first end surface and the second end surface is smaller than the second angle ?2 formed by the second end surface and the third end surface, and the second angle ?2 is 80 to 100 degrees.

Abstract: A microwave assisted magnetic head is equipped with a main magnetic pole that generates a recording magnetic field to be applied to a magnetic recording medium from an end surface forming a portion of an air bearing surface opposed to the magnetic recording medium, a trailing shield that is disposed interposing a write gap at a trailing side of the main magnetic pole, and that forms a magnetic path with the main magnetic pole, two side shields that are disposed at both sides of the main magnetic pole in the cross track direction, respectively, and a spin torque oscillator that is disposed within the write gap. The write gap is configured to substantially linearly extend along the cross track direction when viewed from an air bearing surface side, and is positioned between trailing-side end surfaces of the main magnetic pole and the two side shields, and a leading-side end surface of the trailing shield.

Abstract: A magnetic head includes a microwave-generating element connected to a ground line. The ground line is made shorter by connecting the ground line to a conductive slider substrate so that the microwave-generating element is in a nearly short-circuited end condition. This allows a microwave excitation current to be efficiently supplied to the microwave-generating element, thus enabling effective microwave-assisted recording.

Abstract: A magnetic head includes a main magnetic pole used to apply a recording signal magnetic field to a magnetic recording medium and also includes a microwave line through which a microwave alternating current is transferred. The microwave line is connected to the main magnetic pole. The entire end surface of the main magnetic pole is positioned closer to air bearing surface than a connection portion at which the microwave line and main magnetic pole are mutually connected. Therefore, microwave assisted magnetic recording is possible without deteriorating the recording signal magnetic field.

Abstract: A magnetic recording and reproducing apparatus includes a magnetic recording medium including a recording layer in which at least two magnetic layers are layered on a non-magnetic substrate; and a magnetic head including a main magnetic pole for applying a recording magnetic field in a direction substantially perpendicular to a recording face of the magnetic recording medium and a microwave generating element that generates a microwave magnetic field. The relationship between a thickness Ts of a magnetic layer having a lowest magnetic anisotropy energy among the at least two magnetic layers composing the recording layer of the magnetic recording medium, and a thickness Tt of the recording layer is Ts/Tt?0.2. The microwave generating element applies the microwave magnetic field having a width broader than the width of the recording magnetic field generated by the main magnetic pole of the magnetic head to the magnetic recording medium.

Abstract: A magnetic head includes a main magnetic pole used to apply a recording signal magnetic field to a magnetic recording medium and also includes a microwave line through which a microwave alternating current is transferred. The microwave line is connected to the main magnetic pole. The entire end surface of the main magnetic pole is positioned closer to air bearing surface than a connection portion at which the microwave line and main magnetic pole are mutually connected. Therefore, microwave assisted magnetic recording is possible without deteriorating the recording signal magnetic field.

Abstract: A magnetic recording and reproducing apparatus includes a magnetic recording medium including a recording layer in which at least two magnetic layers are layered on a non-magnetic substrate; and a magnetic head including a main magnetic pole for applying a recording magnetic field in a direction substantially perpendicular to a recording face of the magnetic recording medium and a microwave generating element that generates a microwave magnetic field. The relationship between a thickness Ts of a magnetic layer having a lowest magnetic anisotropy energy among the at least two magnetic layers composing the recording layer of the magnetic recording medium, and a thickness Tt of the recording layer is Ts/Tt?0.2. The microwave generating element applies the microwave magnetic field having a width broader than the width of the recording magnetic field generated by the main magnetic pole of the magnetic head to the magnetic recording medium.

Abstract: A suspension is configured to support a magnetic head slider having a recording head element for recording to a magnetic recording medium and a microwave generating element that applies a high-frequency magnetic field to the magnetic recording medium when recording to the magnetic recording medium is conducted by the recording head element. The suspension includes a flexure that supports the magnetic head slider, and a microwave signal transmission line and a recording signal transmission line that are supported by the flexure. The microwave signal transmission line is connected to the microwave generating element and configured to transmit microwave signals for generating the high-frequency magnetic field, the recording signal transmission line being connected to the recording head element and configured to transmit recording signals. The flexure has a main body part, a support part for the magnetic head slider, and a pair of arm parts that links the main body part and the support part.

Abstract: A magnetic recording device includes a magnetic disk and a magnetic head that performs magnetic recording to the magnetic disk. The magnetic head includes a main magnetic pole layer and a microwave generating element. The magnetic recording device further includes a microwave generating element driving current control circuit. The microwave generating element driving current control circuit, during the magnetic recording, applies a microwave generating element driving current at a first current level to the microwave generating element for a period that is from at the latest a polarity reversal of the recording current before a subsequent polarity reversal of the recording voltage, and thereafter applies another microwave generating element driving current at a second current level, which is smaller than the first current level, to the microwave generating element, or stops the application of the another microwave generating element driving current until the polarity reversal of the recording voltage.

Abstract: A magnetic recording apparatus includes a magnetic recording medium that is provided with a first magnetic layer with magneto crystalline anisotropy energy, a second magnetic layer with magneto crystalline anisotropy energy that is smaller than the magneto crystalline anisotropy energy of the first magnetic layer, and a nonmagnetic metal layer that is positioned between the first magnetic layer and the second magnetic layer and that provides coupling force between the first magnetic layer and the second magnetic layer; and a magnetic head that includes a main pole that applies a recording magnetic field in a direction perpendicular to a film surface of the magnetic recording medium to the magnetic recording medium, and an alternate current (AC) magnetic field generator that applies an AC magnetic field with a frequency of 1-40 GHz to the magnetic recording medium.

Abstract: A suspension is configured to support a magnetic head slider having a recording head element for recording to a magnetic recording medium and a microwave generating element that applies a high-frequency magnetic field to the magnetic recording medium when recording is conducted by the recording head element. The suspension has a flexure that supports the magnetic head slider, a microwave signal transmission line and a recording signal transmission line. The microwave signal transmission line is connected to the microwave generating element and configured to transmit microwave signals for generating the high-frequency magnetic field. The microwave signal transmission line and the recording signal transmission line are supported between the main body part and the support part, a portion of which has a first lamination structure where a first ground layer is conductive and a first insulating layer supports the microwave signal transmission.

Abstract: A microwave assisted magnetic head includes a main magnetic pole; a trailing shield, a main coil for causing the main magnetic pole to generate a perpendicular recording field, at least one secondary coil for generating an in-plane alternate-current (AC) magnetic field with a frequency in a microwave band from a magnetic recording gap between the main magnetic pole and the trailing shield, nonmagnetic films formed on magnetic recording gap facing surfaces that are defined by the main magnetic pole and the trailing shield, the main magnetic pole and the trailing shield being configured with first soft magnetic films, and second soft magnetic films formed further on the surfaces of the nonmagnetic films. The second soft magnetic films have larger anisotropy fields than the first soft magnetic films have.

Abstract: A magnetic head includes a microwave-generating element connected to a ground line. The ground line is made shorter by connecting the ground line to a conductive slider substrate so that the microwave-generating element is in a short-circuited end condition. This allows a microwave excitation current to be efficiently supplied to the microwave-generating-element, thus enabling effective microwave-assisted recording.

Abstract: A magnetic recording device includes a magnetic disk and a magnetic head that performs magnetic recording to the magnetic disk. The magnetic head includes a main magnetic pole layer and a microwave generating element. The magnetic recording device further includes a microwave generating element driving current control circuit. The microwave generating element driving current control circuit, during the magnetic recording, applies a microwave generating element driving current at a first current level to the microwave generating element for a period that is from at the latest a polarity reversal of the recording current before a subsequent polarity reversal of the recording voltage, and thereafter applies another microwave generating element driving current at a second current level, which is smaller than the first current level, to the microwave generating element, or stops the application of the another microwave generating element driving current until the polarity reversal of the recording voltage.

Abstract: Ion irradiation is applied to the surface of a recording layer which has a granular structure containing ferromagnetic particles which are composed of an L10 ordered alloy and a non-magnetic intergranular layer, thereby the ferromagnetic particles in the side of the substrate are transformed into an L10 ordered alloy having a high magnetic anisotropy, and the ferromagnetic particles in the side of the surface of the medium are transformed into an A1 disordered alloy having a low magnetic anisotropy.

Abstract: A head gimbal assembly includes a magnetic head slider provided with a recording head element that applies a recording magnetic field to a magnetic recording medium and a suspension that supports the magnetic head slider. The magnetic head slider further includes a microwave radiation element that radiates a microwave magnetic field from a microwave excitation current that is supplied from a microwave generating circuit, and that applies the microwave magnetic field to the magnetic recording medium when the recording head element applies the recording magnetic field to the magnetic recording medium. The suspension includes a microwave transmission line that transmits the microwave excitation current, and the microwave transmission line is provided with a matching circuit to achieve impedance matching with the microwave radiation element.

Abstract: A magnetic head that writes information to a recording medium includes a magnetic pole layer that generates a writing magnetic field to the recording medium, a microstripline that is disposed in proximity to the magnetic pole layer and to which high frequency current is applied, and a ferromagnetic thin film that is disposed on a portion of the microstripline that faces the recording medium, and that generates a high frequency alternate-current (AC) magnetic field to be applied to the recording medium, using a current magnetic field generated on the microstripline due to the high frequency current.