Magnetic head and magnetic recording device

a magnetic recording device and magnetic head technology, applied in special recording techniques, instruments, transportation and packaging, etc., can solve the problems of difficult to achieve such a high recording density, difficult to reduce the coercivity of the recording area, and temporarily slow down the increase of recording density

Inactive Publication Date: 2009-03-26
KK TOSHIBA
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0013]The present invention has been made in view of these circumstances, and an object thereof is to provide a magnetic head that can restrict the variation of the oscillation frequency of a spin torque oscillator placed in the vicinity of the recording magnetic pole, and a magnetic recording device that has the magnetic head.

Problems solved by technology

However, the problems of heat fluctuations of magnetic recording media became apparent in the early 2000's, and the increase of the recording density temporarily slowed down.
However, achieving such a high recording density is not easy by the perpendicular magnetic recording method by itself, as the problem of heat fluctuations has resurfaced.
Therefore, it is difficult to reduce the coercivity of the recording area.
Therefore, the region where the high-frequency magnetic field generated from the spin torque oscillators is applied is limited to a very small area at a distance of several tens of nanometers from the spin torque oscillators.

Method used

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  • Magnetic head and magnetic recording device
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Examples

Experimental program
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Effect test

first embodiment

[0043]Referring to FIGS. 1 through 8B, a magnetic head in accordance with a first embodiment of the present invention is described. The magnetic head of this embodiment is a magnetic head for assisting a high-frequency magnetic field, and is used with a perpendicular magnetic recording medium.

[0044]FIG. 1 is a cross-sectional view of the magnetic head of this embodiment and a magnetic recording medium, taken along a plane in a direction (the track longitudinal direction) that is perpendicular to a plane facing the magnetic recording medium and is parallel to the moving direction of the magnetic recording medium. FIG. 2 is a cross-sectional view of the magnetic head of this embodiment, taken along a plane in a direction (the track width direction) that is perpendicular to the plane facing the magnetic recording medium and is perpendicular to the moving direction of the magnetic recording medium.

[0045]As shown in FIG. 1, the magnetic recording head of this embodiment includes a reprod...

third modification

[0075]FIG. 11 illustrates a magnetic head in accordance with a third modification of the first embodiment. FIG. 11 is a schematic perspective view of the magnetic head of this modification. The magnetic head of this modification differs from the second modification illustrated in FIG. 10, in that the electromagnetic coils 28b are designed to surround the fourth portions 28a4.

[0076]Like the first embodiment, this modification can also restrict the variation of the spin torque oscillator frequency due to a recording magnetic field.

[0077]In this modification, as the spin torque oscillator 26, it is possible to employ a spin torque oscillator having the electrode layer 265, the oscillator layer 264, the intermediate layer 263, the spin injection layer 262, and the electrode layer 261 stacked in a direction substantially parallel to the direction of the magnetic field applied to the spin torque oscillator 26 by the electromagnet 28, as shown in FIG. 4. It is also possible to employ a spi...

fourth modification

[0078]FIG. 12 illustrates a magnetic head in accordance with a fourth modification of the first embodiment. FIG. 12 is a cross-sectional view of the magnetic head of this modification and a magnetic recording medium, taken along a plane in a direction (the track longitudinal direction) that is perpendicular to the surface of the magnetic recording medium and is parallel to the moving direction of the magnetic recording medium. The magnetic head of this modification differs from the first embodiment illustrated in FIG. 1, in that the writing head unit 20 is replaced with a writing head unit 20A of a single-pole structure. In this writing head unit 20A, the return yoke 24 of the first embodiment illustrated in FIG. 1 is replaced with a return yoke 24A that does not have the front portion (the shield) 24b. Accordingly, in this modification, the cross section taken along the plane in a direction (the track width direction) that is perpendicular to the air bearing surface and is perpendi...

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Abstract

It is made possible to restrict the variation of the oscillation frequency of a spin torque oscillator placed in the vicinity of the recording magnetic pole. A magnetic head includes: a recording magnetic pole to generate a recording magnetic field; a spin torque oscillator formed in the vicinity of the recording magnetic pole; and a magnetic field applying unit configured to apply a magnetic field to the spin torque oscillator. The magnetic field applied to the spin torque oscillator by the magnetic field applying unit is perpendicular to a recording magnetic field generated from the recording magnetic pole.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2007-247966 filed on Sep. 25, 2007 in Japan, the entire contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to a magnetic head having a spin torque oscillator, and a magnetic recording device.[0004]2. Related Art[0005]In the 1990's, the recording density and capacity of HDDs (Hard Disk Drives) dramatically increased, with MR (Magneto-Resistive effect) heads and GMR (Giant Magneto-Resistive effect) heads being put into practical use. However, the problems of heat fluctuations of magnetic recording media became apparent in the early 2000's, and the increase of the recording density temporarily slowed down. In 2005, perpendicular magnetic recording, which is more suitable for high-density recording than in-plane magnetic recording in princi...

Claims

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Application Information

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Patent Type & Authority Applications(United States)
IPC IPC(8): G11B21/02G11B5/127
CPCG11B2005/0005G11B5/314G11B2005/0024Y10T428/1171G11B5/127G11B5/39
Inventor SHIMIZU, MARIKOIWASAKI, HITOSHIYAMADA, KENICHIROAKIYAMA, JUNICHITAKAGISHI, MASAYUKIFUNAYAMA, TOMOMITAKASHITA, MASAHIRO
Owner KK TOSHIBA
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