According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a third magnetic layer provided between the second magnetic layer and the second magnetic pole, a first non-magnetic layer provided between the first and second magnetic layers, a second non-magnetic layer provided between the second and third magnetic layers, a third non-magnetic layer provided between the first magnetic pole and the first magnetic layer, and a fourth non-magnetic layer provided between the third magnetic layer and the second magnetic pole. A first magnetic pole length is shorter than a second magnetic pole length. A first magnetic layer length is longer than a second magnetic layer length.

According to one embodiment, a magnetic recording device includes a magnetic head, a first circuit, a second circuit, a third circuit, and a controller. The magnetic head includes a first magnetic pole, a second magnetic pole, a magnetic element, and a coil. The magnetic element is located between the first magnetic pole and the second magnetic pole. The magnetic element includes a first magnetic layer. The first circuit is configured to supply a coil current to the coil. The second circuit is configured to supply an element current to the magnetic element. The third circuit is configured to detect an electrical resistance of the magnetic element. The controller is configured to control the element current by controlling the second circuit based on the electrical resistance detected by the third circuit.

According to one embodiment, a magnetic head includes a first magnetic pole, a second magnetic pole, and a stacked body provided between the first and second magnetic poles. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the second magnetic pole, a third magnetic layer provided between the second magnetic layer and the second magnetic pole, a first non-magnetic layer provided between the first and second magnetic layers, a second non-magnetic layer provided between the second and third magnetic layers, a third non-magnetic layer provided between the first magnetic pole and the first magnetic layer, and a fourth non-magnetic layer provided between the third magnetic layer and the second magnetic pole. A first magnetic pole length is shorter than a second magnetic pole length. A first magnetic layer length is longer than a second magnetic layer length.

According to one embodiment, a magnetic recording device for utilizing assisted magnetic recording includes a magnetic head, a first circuit, a second circuit, a third circuit, and a controller. The magnetic head includes a first magnetic pole, a second magnetic pole, a magnetic element, and a coil. The magnetic element is located between the first magnetic pole and the second magnetic pole. The magnetic element includes a first magnetic layer. The first circuit is configured to supply a coil current to the coil. The second circuit is configured to supply an element current to the magnetic element. The third circuit is configured to detect an electrical resistance of the magnetic element. The controller is configured to control the element current by controlling the second circuit based on the electrical resistance detected by the third circuit.

A spin transfer torque reversal assisted magnetic recording (STRAMR) structure is disclosed wherein two flux change layers (FCL1 and FCL2) are formed within a write gap (WG) and between a main pole (MP) trailing side and trailing shield (TS). Each FCL has a magnetization that flips to a direction substantially opposing a WG field when a direct current of sufficient current density is applied across the STRAMR device thereby increasing reluctance in the WG and producing a larger write field output at the air bearing surface. A reference layer (RL1) is used to reflect spin polarized electrons that exert spin torque on FCL1 and cause FCL1 magnetization to flip. A second reference layer (or the MP or TS) is employed to reflect spin polarize electrons that generate spin torque on FCL2 and flip FCL2 magnetization. Non-spin polarization preserving layers and spin polarization preserving layers are also in the STRAMR structure.

According to one embodiment, a magnetic head includes a magnetic pole, a first shield, a magnetic layer, and first and second conductive layers. The magnetic layer is provided between the magnetic pole and the first shield. The first conductive layer contacts the first shield and the magnetic layer, is provided between the first shield and the magnetic layer, and includes at least one element selected from Cu, Ag, and Au. The second conductive layer is provided between the magnetic pole and the magnetic layer. The second conductive layer includes first and second regions. The first region contacts the magnetic layer and includes at least one first element selected from Cu, Ag, Au, Al, Ti, Ru, Mg, and V. The second region is provided between the first region and the magnetic pole and includes at least one second element selected from Ta, Pt, W, Mo, Ir, Cr, Tb, Rh, and Pd. This arrangement allows the magnetic field emitted from the magnetic pole to be oriented efficiently towards the magnetic recording medium and recording density to be increased.

According to one embodiment, a magnetic head includes a magnetic pole, a first shield, a magnetic layer, first and second conductive layers. The magnetic layer is provided between the magnetic pole and the first shield. The first conductive layer contacts the first shield and the magnetic layer, is provided between the first shield and the magnetic layer, and includes at least one selected from Cu, Ag, and Au. The second conductive layer is provided between the magnetic pole and the magnetic layer. The second conductive layer includes first and second regions. The first region contacts the magnetic layer and includes at least one first element selected from Cu, Ag, Au, Al, Ti, Ru, Mg, and V. The second region is provided between the first region and the magnetic pole and includes at least one second element selected from Ta, Pt, W, Mo, Ir, Cr, Tb, Rh, and Pd.