Abstract: According to one embodiment, a magnetic recording head includes a magnetic pole and a shield. The shield has a first opposing surface opposing the magnetic pole. The first opposing surface includes a first opposing portion. The magnetic pole and the first opposing portion overlap in a first direction from the magnetic pole toward the shield. The first opposing portion includes a first protrusion.

Abstract: A magnetic head according to an embodiment includes: a spin valve element with three terminals including a nonmagnetic base layer, a first terminal including a first magnetic layer, a second terminal including a second magnetic layer, and a third terminal including a third magnetic layer; and a slider including a first external lead terminal connecting to the first terminal, a second external lead terminal connecting to the second terminal, and a third external lead terminal connecting to the third terminal, in an operation, a first current being caused to flow from the second external lead terminal to the third terminal via the second terminal and the nonmagnetic base layer, and a second current that is lower than the first current being caused to flow to the first terminal.

Abstract: According to one embodiment, a magnetic recording device includes a magnetic recording medium and a magnetic head. The magnetic head includes a magnetic pole and a trailing shield. The magnetic pole has a medium-opposing surface opposing the magnetic recording medium. The medium-opposing surface has a magnetic pole length along a first direction. The first direction is from the magnetic pole toward the trailing shield. The magnetic pole length is shorter than a track pitch of the magnetic recording medium.

Abstract: A microwave-assisted magnetic recording head according to an embodiment includes: a magnetic pole; a magnetic shield including a first portion and a second portion connecting to the first portion, a gap being present between the first portion and the magnetic pole; a recording coil disposed to at least one of the magnetic pole and the magnetic shield; and a spin torque oscillator including a nonmagnetic intermediate layer extending within and outside the gap, an oscillation layer disposed on a portion of the nonmagnetic intermediate layer in the gap, and a spin injection layer in which a magnetization direction is pinned and which is disposed on a portion of the nonmagnetic intermediate layer outside the gap so as to be separated from the oscillation layer.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium and a magnetic head. The magnetic recording medium includes a first track including a first sub-track extending along a first direction, and a second sub-track extending along the first direction. The second sub-track is arranged with the first sub-track in a second direction intersecting the first direction. The magnetic head includes a recording unit and a reproducing unit. The recording unit records information in the magnetic recording medium. The reproducing unit reproduces the information recorded in the magnetic recording medium. The recording unit includes a magnetic pole, a write shield separated from the magnetic pole in the first direction, and a side shield separated from the magnetic pole in the second direction. The reproducing unit includes a reproducing element having a reproducing width along the second direction.

Abstract: According to one embodiment, a magnetoresistance effect element includes first and second shields, first and second side magnetic units, a stacked body, and a hard bias unit. The first side magnetic unit includes a first soft magnetic layer, a first nonmagnetic intermediate layer, and a second soft magnetic layer. The second side magnetic unit includes a third soft magnetic layer, a second nonmagnetic intermediate layer, and a fourth soft magnetic layer. The stacked body includes a fifth ferromagnetic layer, a third nonmagnetic intermediate layer, and a sixth ferromagnetic layer. The hard bias unit is provided between the first and second shields. A first distance between the first and fifth magnetic layers is shorter than a second distance between the second and sixth magnetic layers. A third distance between the third and fifth magnetic layers is shorter than a fourth distance between the fourth and sixth magnetic layers.

Abstract: According to one embodiment, a magnetic recording head includes a magnetic pole and a shield. The shield has a first opposing surface opposing the magnetic pole. The first opposing surface includes a first opposing portion. The magnetic pole and the first opposing portion overlap in a first direction from the magnetic pole toward the shield. The first opposing portion includes a first protrusion.

Abstract: A magnetic head of an embodiment includes a stack, side shields, and a first and a second magnetic shield. The stack includes a pin layer having a fixed magnetization direction, a first free layer having a magnetization direction to change in accordance with an external magnetic field, a second free layer antiferromagnetically exchange-coupled with the first free layer and having a magnetization direction to change in accordance with the field, and an antiferromagnetic layer exchange-coupled with the second free layer. A magnetic field is applied from the side shields to the first and second free layers, and a direction of the magnetic field is substantially parallel to the magnetization direction of one of the first and second free layers and substantially antiparallel to the magnetization direction of the other, and a magnetic volume of the one is larger than a magnetic volume of the other.

Abstract: A magnetoresistive element according to an embodiment includes: a multilayer element including a first magnetic layer, a magnetization direction of the first magnetic layer being pinned, a nonmagnetic layer disposed on the first magnetic layer, a second magnetic layer disposed in a first region on the nonmagnetic layer, a magnetization direction of the second magnetic layer being pinned and antiparallel to the magnetization direction of the first magnetic layer, and a third magnetic layer disposed in a second region that is different from the first region on the nonmagnetic layer near one of two opposite end faces of the nonmagnetic layer, a magnetization direction of the third magnetic layer being changeable by an external magnetic field, a lower face of the nonmagnetic layer being in contact with an upper face of the first magnetic layer.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium and a magnetic head. The magnetic recording medium includes a first track including a first sub-track extending along a first direction, and a second sub-track extending along the first direction. The second sub-track is arranged with the first sub-track in a second direction intersecting the first direction. The magnetic head includes a recording unit and a reproducing unit. The recording unit records information in the magnetic recording medium. The reproducing unit reproduces the information recorded in the magnetic recording medium. The recording unit includes a magnetic pole, a write shield separated from the magnetic pole in the first direction, and a side shield separated from the magnetic pole in the second direction. The reproducing unit includes a reproducing element having a reproducing width along the second direction.

Abstract: An example magnetic recording apparatus includes a magnetic recording medium, a magnetic recording head and a signal processor. The magnetic recording head includes a first magnetic pole to apply a recording magnetic field to the magnetic recording medium; a spin torque oscillator arranged parallel to the first magnetic pole; and a first coil to magnetize the first magnetic pole. The signal processor writes and reads a signal on the magnetic recording medium by using the magnetic recording head and includes a first current circuit to supply a recording current to the first coil, the recording current including a recording signal to be recorded on the magnetic recording medium. The recording current includes either one of a signal changing at a frequency higher than that of the recording signal, and a signal having the same frequency as the recording signal and changing an absolute value thereof in one cycle.

Abstract: A microwave-assisted magnetic recording head according to an embodiment includes: a magnetic pole; a magnetic shield including a first portion and a second portion connecting to the first portion, a gap being present between the first portion and the magnetic pole; a recording coil disposed to at least one of the magnetic pole and the magnetic shield; and a spin torque oscillator including a nonmagnetic intermediate layer extending within and outside the gap, an oscillation layer disposed on a portion of the nonmagnetic intermediate layer in the gap, and a spin injection layer in which a magnetization direction is pinned and which is disposed on a portion of the nonmagnetic intermediate layer outside the gap so as to be separated from the oscillation layer.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, a recording unit, and a reproducing unit. The magnetic recording medium includes a first track including first and second sub-tracks extending in a first direction. The second sub-track is arranged with the first sub-track in a second direction intersecting the first direction. The recording unit records information in the first and second sub-tracks. The reproducing unit reproduces the information recorded in the first and second sub-tracks while opposing the first, second sub-tracks, and a boundary between the first and second sub-tracks. The first sub-track includes first magnetic recording components including first and second components. The second sub-track includes second magnetic recording components including third and fourth components. A first recording symbol is formed of the first and third components. A second recording symbol is formed of the second and fourth components.

Abstract: According to one embodiment, a magnetic recording head records information in a magnetic recording medium by shingled magnetic recording. The magnetic recording head includes a magnetic pole and a shield opposing the magnetic pole. The magnetic pole has a shield-opposing surface opposing the shield. The shield-opposing surface includes a first portion and a second portion. A position of the second portion in a track width direction is different from a position of the first portion in the track width direction, the track width direction intersecting a first direction from the magnetic pole toward the shield. The first portion records the information in the magnetic recording medium after the second portion in the shingled magnetic recording. A first distance between the first portion and the shield is shorter than a second distance between the second portion and the shield. The shield-opposing surface is tilted with respect to the first direction.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes a magnetic recording medium, a recording unit, and a reproducing unit. The magnetic recording medium includes a first track including first and second sub-tracks extending in a first direction. The second sub-track is arranged with the first sub-track in a second direction intersecting the first direction. The recording unit records information in the first and second sub-tracks. The reproducing unit reproduces the information recorded in the first and second sub-tracks while opposing the first, second sub-tracks, and a boundary between the first and second sub-tracks. The first sub-track includes first magnetic recording components including first and second components. The second sub-track includes second magnetic recording components including third and fourth components. A first recording symbol is formed of the first and third components. A second recording symbol is formed of the second and fourth components.

Abstract: A magnetic head according to an embodiment includes: a non-local spin valve element with three terminals including a nonmagnetic base layer, a first terminal including a first magnetic layer, a second terminal including a second magnetic layer, and a third terminal including a third magnetic layer; and a slider including a first external lead terminal connecting to the first terminal, a second external lead terminal connecting to the second terminal, and a third external lead terminal connecting to the third terminal, in an operation, a first current being caused to flow from the second external lead terminal to the third terminal via the second terminal and the nonmagnetic base layer, and a second current that is lower than the first current being caused to flow to the first terminal.

Abstract: A magnetoresistive element according to an embodiment includes: a multilayer element including a first magnetic layer, a magnetization direction of the first magnetic layer being pinned, a nonmagnetic layer disposed on the first magnetic layer, a second magnetic layer disposed in a first region on the nonmagnetic layer, a magnetization direction of the second magnetic layer being pinned and antiparallel to the magnetization direction of the first magnetic layer, and a third magnetic layer disposed in a second region that is different from the first region on the nonmagnetic layer near one of two opposite end faces of the nonmagnetic layer, a magnetization direction of the third magnetic layer being changeable by an external magnetic field, a lower face of the nonmagnetic layer being in contact with an upper face of the first magnetic layer.

Abstract: A magnetic head of an embodiment includes a stack, side shields, and a first and a second magnetic shield. The stack includes a pin layer having a fixed magnetization direction, a first free layer having a magnetization direction to change in accordance with an external magnetic field, a second free layer antiferromagnetically exchange-coupled with the first free layer and having a magnetization direction to change in accordance with the field, and an antiferromagnetic layer exchange-coupled with the second free layer. A magnetic field is applied from the side shields to the first and second free layers, and a direction of the magnetic field is substantially parallel to the magnetization direction of one of the first and second free layers and substantially antiparallel to the magnetization direction of the other, and a magnetic volume of the one is larger than a magnetic volume of the other.

Abstract: A magnetic head of an embodiment has first and second magnetic shields, a stack, a side shield, and an antiferromagnetic layer. The stack has a pin layer, a nonmagnetic layer, and first and second free layers. The second free layer is antiferromagnetically exchange coupled to the first free layer and is exchange coupled to the antiferromagnetic layer. The side shield is exchange coupled to the antiferromagnetic layer.

Abstract: A magnetic head of an embodiment includes: a first electrode being a magnetic body having a magnetic shielding property; a first signal detector disposed on the first electrode and being a differential magnetoresistive effect element; a second electrode disposed on the first signal detector; an insulating layer disposed on the second electrode; a third electrode disposed on the insulating layer; a second signal detector disposed on the third electrode and being a differential magnetoresistive effect element; and a fourth electrode disposed on the second signal detector and being a magnetic body having a magnetic shielding property. At least one of the second electrode and the third electrode is a nonmagnetic metal.