According to one embodiment, a magnetic recording head includes a magnetic pole, a stacked body, and a first non-magnetic layer. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the magnetic pole, and a non-magnetic intermediate layer provided between the first magnetic layer and the second magnetic layer. The first non-magnetic layer is provided between the second magnetic layer and the magnetic pole, and contacts the magnetic pole and the second magnetic layer. The first magnetic layer has a first thickness and a first saturation magnetic flux density. The second magnetic layer has a second thickness and a second saturation magnetic flux density. A second product of the second thickness and the second saturation magnetic flux density is larger than a first product of the first thickness and the first saturation magnetic flux density.

According to one embodiment, a magnetic recording head includes a magnetic pole, a stacked body, and a first non-magnetic layer. The stacked body includes a first magnetic layer, a second magnetic layer provided between the first magnetic layer and the magnetic pole, and a non-magnetic intermediate layer provided between the first magnetic layer and the second magnetic layer. The first non-magnetic layer is provided between the second magnetic layer and the magnetic pole, and contacts the magnetic pole and the second magnetic layer. The first magnetic layer has a first thickness and a first saturation magnetic flux density. The second magnetic layer has a second thickness and a second saturation magnetic flux density. A second product of the second thickness and the second saturation magnetic flux density is larger than a first product of the first thickness and the first saturation magnetic flux density.

A dual perpendicular magnetic recording writer is disclosed wherein the better of two writers on a slider is determined by performance testing, and is then integrated into a head gimbal assembly. Main pole layers in the two writers are separated by a cross-track width<10 microns to minimize read-write offset. Each of the driving coil (DC) and bucking coil (BC) have two outer portions forming a U shape with a front side, and each have a center portion connected to the front side proximate to an air bearing surface and a backend contacting an interconnect. A write current passes from a BC outer portion below the main pole in the selected writer through the BC center portion to the interconnect, and then through the DC center portion to a DC outer portion above the main pole in the selected writer. Area density capability mean and sigma are improved.

A dual perpendicular magnetic recording writer is disclosed wherein the better of two writers on a slider is determined by performance testing, and is then integrated into a head gimbal assembly. Main pole layers in the two writers are separated by a cross-track width<10 microns to minimize read-write offset. Each of the driving coil (DC) and bucking coil (BC) have two outer portions forming a U shape with a front side, and each have a center portion connected to the front side proximate to an air bearing surface and a backend contacting an interconnect. A write current passes from a BC outer portion below the main pole in the selected writer through the BC center portion to the interconnect, and then through the DC center portion to a DC outer portion above the main pole in the selected writer. Area density capability mean and sigma are improved.

This magnetic head, which reads and writes magnetic information, prevents a signal from being read between the magnetic head and the write circuit during reading of magnetic information. A card reader 1 is provided with a magnetic head 6 which reads and writes magnetic information. Bidirectional diodes 54A, 54B are arranged inside of a head case 21 of the magnetic head 6. A write signal from a write circuit 72 is inputted via the bidirectional diodes 54A, 54B to a writing coil 34 wound around a core 32 of the magnetic head 6. The bidirectional diodes 54A, 54B and a demodulation IC 61 are mounted on a first board surface 62A of a control circuit board 62, and the control circuit board 62 is fixed to the head case 21 so that the bidirectional diodes 54A, 54B and the demodulation IC 61 are covered by the head case 21.

This magnetic head, which reads and writes magnetic information, prevents a signal from being read between the magnetic head and the write circuit during reading of magnetic information. A card reader 1 is provided with a magnetic head 6 which reads and writes magnetic information. Bidirectional diodes 54A, 54B are arranged inside of a head case 21 of the magnetic head 6. A write signal from a write circuit 72 is inputted via the bidirectional diodes 54A, 54B to a writing coil 34 wound around a core 32 of the magnetic head 6. The bidirectional diodes 54A, 54B and a demodulation IC 61 are mounted on a first board surface 62A of a control circuit board 62, and the control circuit board 62 is fixed to the head case 21 so that the bidirectional diodes 54A, 54B and the demodulation IC 61 are covered by the head case 21.

A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a spin torque oscillator (STO) element. The data storage device further comprises a differential amplifier comprising a first input coupled to a first end of the STO element and a second input coupled to a second end of the STO element. A bias current is applied to the STO element, and the bias current is adjusted. A resistance delta of the STO element is detected based on an output of the differential amplifier, wherein the resistance delta corresponds to a bias current level when the STO begins to oscillate.

A spin transfer torque (STT) device has a free ferromagnetic layer that includes a Heusler alloy layer and a template layer beneath and in contact with the Heusler alloy layer. The template layer may be a ferromagnetic alloy comprising one or more of Co, Ni and Fe and the element X, where X is selected from one or more of Ta, B, Hf, Zr, W, Nb and Mo. A CoFe nanolayer may be formed below and in contact with the template layer. The STT device may be a spin-torque oscillator (STO), like a STO incorporated into the write head of a magnetic recording disk drive. The STT device may also be a STT in-plane or perpendicular magnetic tunnel junction (MTJ) cell for magnetic random access memory (MRAM). The template layer reduces the critical current density of the STT device.

A spin transfer torque (STT) device has a free ferromagnetic layer that includes a Heusler alloy layer and a template layer beneath and in contact with the Heusler alloy layer. The template layer may be a ferromagnetic alloy comprising one or more of Co, Ni and Fe and the element X, where X is selected from one or more of Ta, B, Hf, Zr, W, Nb and Mo. A CoFe nanolayer may be formed below and in contact with the template layer. The STT device may be a spin-torque oscillator (STO), like a STO incorporated into the write head of a magnetic recording disk drive. The STT device may also be a STT in-plane or perpendicular magnetic tunnel junction (MTJ) cell for magnetic random access memory (MRAM). The template layer reduces the critical current density of the STT device.

A slider comprises an air bearing surface (ABS) and is configured to interact with a magnetic recording medium. A writer is provided on the slider and comprises a write coil having a media-facing surface situated at the ABS. Cooling arms project laterally from peripheral surfaces of the write coil and extend along the ABS. The media-facing surface of the write coil and the cooling arms are exposed to the ABS to facilitate increased cooling of the write coil at the ABS.