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.

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 medium includes a substrate, an auxiliary layer formed on the substrate, and at least one perpendicular magnetic recording layer formed on the auxiliary layer. The perpendicular magnetic recording layer includes a magnetic dot pattern. The perpendicular magnetic recording layer is made of an alloy material containing one element selected from iron and cobalt, and one element selected from platinum and palladium. This alloy material has the L10 structure, and is (001)-oriented. The auxiliary layer includes a dot-like first region covered with the magnetic dot pattern, and a second region not covered with the magnetic dot pattern. The first region is made of a (100)-oriented nickel oxide. The second region contains nickel used in the first region as a main component.

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: 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 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: According to one embodiment, a magnetic recording and reproducing device includes magnetic recording medium and a magnetic head. The magnetic recording medium includes a first surface. A plurality of bits is provided in the first surface. Each of the bits has a direction of magnetization corresponding to recorded information. The magnetic head includes a reproducing unit. The reproducing unit senses the direction of magnetization. The reproducing unit includes a first shield, a second shield, a first magnetic layer, a second magnetic layer, a third magnetic layer, a fourth magnetic layer, an intermediate layer, a first nonmagnetic layer, and a second nonmagnetic layer. The first and the second nonmagnetic layers include at least one selected from ruthenium, copper, and tantalum. A distance between the first shield and the second shield is not less than 3 times and not more than 7 times a length of each of the bits.

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.

Abstract: According to one embodiment, a magnetic recording and reproducing device includes magnetic recording medium and a magnetic head. The magnetic recording medium includes a first surface. A plurality of bits is provided in the first surface. Each of the bits has a direction of magnetization corresponding to recorded information. The magnetic head includes a reproducing unit. The reproducing unit senses the direction of magnetization. The reproducing unit includes a first shield, a second shield, a first magnetic layer, a second magnetic layer, a third magnetic layer, a fourth magnetic layer, an intermediate layer, a first nonmagnetic layer, and a second nonmagnetic layer. The first and the second nonmagnetic layers include at least one selected from ruthenium, copper, and tantalum. A distance between the first shield and the second shield is not less than 3 times and not more than 7 times a length of each of the bits.

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: A magnetoresistive element according to an embodiment includes: a magnetoresistance effect film including: a first magnetic film; a second magnetic film; and an intermediate film of a nonmagnetic material disposed between the first magnetic film and the second magnetic film, at least one of the first magnetic film and the second magnetic film being formed of a material expressed as AxB1?x(65 at %?x?85 at %) where A is an alloy containing Co and at least one element selected from Fe and Mn, and B is an alloy containing Si or Ge, a Si concentration in the at least one of the first magnetic film and the second magnetic film decreasing and a Ge concentration increasing as a distance from the intermediate film increases.

Abstract: A magnetic head according to an embodiment includes a first magnetic shield and a second magnetic shield that are opposed to each other, and a magnetoresistive film arranged between the first magnetic shield and the second magnetic shield, and including a first magnetic layer including a first metal layer that contains 90 at. % or more of Fe and a first Heusler alloy layer, a second magnetic layer arranged on a side of the first Heusler alloy layer opposite from the first magnetic layer, and an intermediate layer arranged between the first Heusler alloy layer and the second magnetic layer.

Abstract: A magnetoresistive element according to an embodiment includes: a magnetoresistance effect film including: a first and second magnetic films; and an intermediate film disposed between the first and second magnetic films, at least one of the first and second magnetic films being formed of a Heusler alloy expressed as Co100-x(AyB1.0-y)x (40 at %?x?60 at %, 0.3?y?0.7) where A is an alloy containing at least Fe and Mn, and B is an alloy containing at least Si, Al, and Ge, a composition of the at least one of the first and second magnetic films being changed in a film-thickness direction so that a ratio of Fe/(Fe+Mn) is less than 60% in a first region disposed near an interface with the intermediate film in the film-thickness direction, and is 60% or more in a second region that is disposed at more distance from the interface than the first region in the film-thickness direction.

Abstract: According to one embodiment, a magnetoresistance effect element includes first and second shields, a stacked body and a hard bias unit. The stacked body includes first and second magnetic layers, an intermediate layer and a first Ru layer. A magnetization of the first magnetic layer is changeable. A magnetization of the second magnetic layer is changeable. The intermediate layer is nonmagnetic. The first Ru layer is provided between the first shield and the first magnetic layer. A thickness of the first Ru layer is not less than 1.5 nanometers and not more than 2.5 nanometers. The hard bias unit is provided between the first shield and the second shield. A first direction from the first shield toward the second shield intersects a second direction from the stacked body toward the hard bias unit.

Abstract: A magnetoresistive element according to an embodiment includes: a magnetoresistance effect film including: a first magnetic film; a second magnetic film; and an intermediate film of a nonmagnetic material disposed between the first magnetic film and the second magnetic film, at least one of the first magnetic film and the second magnetic film being formed of a material expressed as AxB1-x(65 at %?x?85 at %) where A is an alloy containing Co and at least one element selected from Fe and Mn, and B is an alloy containing Si or Ge, a Si concentration in the at least one of the first magnetic film and the second magnetic film decreasing and a Ge concentration increasing as a distance from the intermediate film increases.

Abstract: A magnetoresistive element according to an embodiment includes: a magnetoresistance effect film including: a first and second magnetic films; and an intermediate film disposed between the first and second magnetic films, at least one of the first and second magnetic films being formed of a Heusler alloy expressed as Co100-x(AyB1.0-y)x (40 at %?x?60 at %, 0.3?y?0.7) where A is an alloy containing at least Fe and Mn, and B is an alloy containing at least Si, Al, and Ge, a composition of the at least one of the first and second magnetic films being changed in a film-thickness direction so that a ratio of Fe/(Fe+Mn) is less than 60% in a first region disposed near an interface with the intermediate film in the film-thickness direction, and is 60% or more in a second region that is disposed at more distance from the interface than the first region in the film-thickness direction.

Abstract: According to one embodiment, a magneto-resistance effect element includes: a first shield; a second shield; a first side shield layer; a second side shield layer; a stacked body; a first shield guide layer; and a second shield guide layer. The first shield guide layer includes a fifth magnetic layer provided between the first side shield layer and the stacked body. The second shield guide layer includes a sixth magnetic layer provided between the second side shield layer and the stacked body. A distance between the first side shield layer and the first shield guide layer is shorter than a distance between the stacked body and the first shield guide layer. A distance between the second side shield layer and the second shield guide layer is shorter than a distance between the stacked body and the second shield guide layer.

Abstract: According to one embodiment, a magnetoresistance effect element includes a first shield, a second shield, a stacked unit, and a hard bias unit. The stacked unit includes a first magnetic layer provided between the first shield and the second shield, a second magnetic layer provided between the first magnetic layer and the second shield, and an intermediate layer provided between the and second magnetic layers. The hard bias unit is provided between the first shield and the second shield to be arranged with the stacked unit. A crystal orientation plane of the first magnetic layer in a film surface perpendicular direction is a cubic (110) plane. The first magnetic layer includes a first stacked body including a first Fe layer and a first Co layer stacked along the first direction, and a first Heusler alloy layer stacked with the first stacked body along the first direction.

Abstract: According to one embodiment, a magnetoresistance effect element includes a first shield, a second shield, a stacked unit, and a hard bias unit. The stacked unit includes a first magnetic layer provided between the first shield and the second shield, a second magnetic layer provided between the first magnetic layer and the second shield, and an intermediate layer provided between the and second magnetic layers. The hard bias unit is provided between the first shield and the second shield to be arranged with the stacked unit. A crystal orientation plane of the first magnetic layer in a film surface perpendicular direction is a cubic (110) plane. The first magnetic layer includes a first stacked body including a first Fe layer and a first Co layer stacked along the first direction, and a first Heusler alloy layer stacked with the first stacked body along the first direction.