According to one embodiment, a magnetic disk device includes: a disk; a head including a main magnetic pole, a write shield that faces the main magnetic pole in a first direction and is separated from the main magnetic pole by a gap, a first assist element that is disposed in the gap and a second assist element that is disposed in the gap and is positioned relative to the first assist element in a second direction intersecting the first direction; and a controller configured to: cause a first assist energy from the first assist element to be applied to the disk and affect a coercive force of the disk; and cause a second assist energy from the second assist element to be applied to the disk and affect a coercive force of the disk, wherein the first assist energy is different from the second assist energy.

Embodiments of the present disclosure generally relate to a magnetic media drive employing a magnetic recording device. The magnetic recording device comprises a trailing gap disposed adjacent to a first surface of a main pole, a first side gap disposed adjacent to a second surface of the main pole, a second side gap disposed adjacent to a third surface of the main pole, and a leading gap disposed adjacent to a fourth surface of the main pole. A side shield surrounds the main pole and comprises a heavy metal first layer and a magnetic second layer. The first layer surrounds the first, second, and third surfaces of the main pole, or the second, third, and fourth surfaces of the main pole. The second layer surrounds the second and third surfaces of the main pole, and may further surround the fourth surface of the main pole.

A magnetic recording write head and system has a spin-torque oscillator (STO) located between the write head's write pole and trailing shield. The STO's ferromagnetic free layer is located near the write pole with a multilayer seed layer between the write pole and the free layer. The STO's nonmagnetic spacer layer is between the free layer and the STO's ferromagnetic polarizer. The polarizer may be the trailing shield of the write head, one or more separate polarizer layers, or combinations thereof. The STO electrical circuitry causes electron flow from the write pole to the trailing shield. The multilayer seed layer removes the spin polarization of electrons from the write pole, which enables electrons reflected from the polarizer layer to become spin polarized, which creates the spin transfer torque on the magnetization of the free layer. The multilayer seed layer includes a Mn or a Mn-alloy layer.

According to one embodiment, a magnetic disk device includes a recording medium, a recording head including a main magnetic pole, a write shield magnetic pole, a coil, and a spin torque oscillator provided between the main magnetic pole and the write shield magnetic pole and a controller including a record current supply circuit and a drive current supply circuit. The controller executes a process of monitoring variation of a resistance value of the spin torque oscillator while increasing the record current in a state in which the spin torque oscillator is energized and detecting a record current value when the resistance value is increased most largely, and a process of setting the detected record current value to a lower limit of the record current supplied to the coil.

According to one embodiment, a magnetic head includes first and second shields, a magnetic pole, and a trailing shield. The magnetic pole is provided between the first and second shields. The trailing shield is separated from the magnetic pole. The first shield includes first magnetic layers and first nonmagnetic layers arranged alternately along a first stacking direction. The first nonmagnetic layers include at least one selected from the group consisting of Ru, Cu, and Cr. Thicknesses of the first nonmagnetic layers each is not less than 0.3 nanometers and not more than 2.2 nanometers. The second shield includes second magnetic layers and second nonmagnetic layers arranged alternately along a second stacking direction. The second nonmagnetic layers include at least one selected from the group consisting of Ru, Cu, and Cr. Thicknesses of the second nonmagnetic layers each is not less than 0.3 nanometers and not more than 2.2 nanometers.

Devices having an air bearing surface (ABS), the device including a near field transducer, the near field transducer having a peg and a disc, the peg having a region adjacent the ABS, the peg including a plasmonic material selected from gold (Au), silver (Ag), copper (Cu), ruthenium (Ru), rhodium (Rh), aluminum (Al), or combinations thereof; and at least one other secondary atom selected from germanium (Ge), tellurium (Te), aluminum (Al), antimony (Sb), tin (Sn), mercury (Hg), indium (In), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), silver (Ag), chromium (Cr), cobalt (Co), and combinations thereof, wherein a concentration of the secondary atom is higher at the region of the peg adjacent the ABS than a concentration of the secondary atom throughout the bulk of the peg, and a method of forming NFT thereof.

A magnetic writer includes a high magnetic moment write pole layer on a main write pole, the write pole layer including a proximal end recessed from the air bearing surface, and a Wide Area Track Erasure (WATER) reservoir recessed from the proximal end of the write pole layer and transverse to a longitudinal direction of the main write pole. The write pole layer may be conformal in shape to, but have smaller dimensions relative to, the main write pole, such that a distance between their outer surfaces is generally constant in a flare region. The WATER reservoir width, in a cross-track direction, may be greater than or equal to the maximum width of the main write pole.

A write pole structure includes a write pole and a trailing shield wherein the write pole includes a high magnetic moment (HMM) material layer on a surface of the write pole facing the trailing shield, wherein the HMM material layer includes a laminated layer including a rare earth material layer and a transition metal layer.

An apparatus according to one embodiment includes a magnetic sensor structure, a magnetic shield having at least one laminate pair comprising a magnetic layer and an electrically nonconductive nonmagnetic layer, and a nonmagnetic spacer layer between the sensor structure and the magnetic shield. In one embodiment, a deposition thickness of the nonconductive nonmagnetic layer in each laminate pair is about 10% or less of a total deposition thickness of the laminate pair. In another embodiment, a deposition thickness of the nonconductive nonmagnetic layer in each laminate pair is between about 1 and about 12 nanometers. In yet another embodiment, the magnetic shield has at least one second laminate pair, and a nonlaminated magnetic portion sandwiched between the at least one laminate pair and the at least one second laminate pair.

An apparatus has a main pole layer of magnetic material, a second layer of magnetic material, a first gap layer of non-magnetic material between the main pole layer and the second layer of magnetic material, and a second gap layer of non-magnetic material disposed between the main pole layer and the second layer of magnetic material. The second gap layer of non-magnetic material can be directly adjacent to the second layer of magnetic material. In accordance with one embodiment, this allows the gap to serve as a non-magnetic seed for the second layer of magnetic material. A method of manufacturing such a device is also described.