Hgst Netherlands, B.v.

Western Digital Technologies, Inc.

Hitachi, Ltd.

Hsgt Netherlands B.v.

Keiichi Nagasaka

Yo Sato

Masato Shiimoto

Masashige Sato

Susumu Okamura

Masukazu Igarashi

Masato Matsubara

Masato Shimoto

Katsuro Watanabe

Nobumasa Nishiyama

Mikito Sugiyama

Hiroyuki Katada

Akira Morinaga

Masukaza Igarashi

Masao Shiimoto

Yuta Udou

A magnetic field-assisted magnetic recording (MAMR) head is provided, which includes a recording main pole, a seed layer, and a spin torque oscillator (STO) positioned over the main pole, in this order, in a stacking direction from a leading side to a trailing side of the recording head. The STO comprises a spin polarized layer (SPL), an interlayer with fcc structure, and a field generating layer (FGL), in this order in the stacking direction. The FGL comprises a low magnetic flux density interface (LMFDI) layer with bcc structure that directly contacts the interlayer.

Low magnetic flux density interface layer for spin torque oscillator

A magnetic field-assisted magnetic recording (MAMR) head is provided, which includes a recording main pole and a texture control layer (TCL), a seed control layer, and a spin torque oscillator (STO) positioned over the main pole, in this order, in a stacking direction from a leading side to a trailing side of the recording head. The STO has a crystallographic preferred growth orientation and includes a spin polarized layer (SPL). The TCL may include a Cu layer.

Texture-control layer for spin torque oscillator

A magnetic write head having a spin torque oscillator with a magnetic field sensor for accurately determining magnetic field oscillation frequency. The spin torque oscillator has one or more tunnel junction (TMR) sensors formed at the side of the spin torque oscillator. The TMR sensor advantageously detects a magnetic field signal that is an additive signal of both fields from the spin polarization layer and the magnetic field generation layer, thereby providing efficient detection of magnetic field and associated oscillation frequency.

Microwave assisted magnetic recording head having spin torque oscillator frequency detection

A magnetic oscillator for use in Microwave Assisted Magnetic Recording (MAMR). The magnetic oscillator can be a spin torque oscillator and includes a magnetic spin polarization layer, a magnetic field generation layer and a non-magnetic intermediate layer sandwiched between the magnetic spin polarization layer and the magnetic field generation layer. The non-magnetic intermediate layer is constructed of a material that provides improved performance, increased lifespan and thermal robustness. The magnetic intermediate layer is constructed of an alloy of Ag and an element X. More preferably the element X can be Sn or Zn.

Spin torque oscillator with high spin torque efficiency and reliability

The embodiments disclosed generally relate to an STO structure for a magnetic head. The STO structure has an FGL having a greater thickness than the SPL. The SPL may have multiple layers. In one embodiment, a MAMR head comprises a main pole; a trailing shield; and an STO coupled between the main pole and the trailing shield. The STO includes: a first magnetic layer having a first thickness; a non-magnetic spacer layer coupled to the first magnetic layer; and a second magnetic layer having a second thickness and coupled to the non-magnetic spacer layer, wherein the first thickness is greater than the second thickness, wherein a current is charged from the first magnetic layer to the second magnetic layer, and wherein a vertical magnetic anisotropy field of the second magnetic film is less than 0 kOe.

AF-mode STO with negative Hk spin polarization layer

Embodiments disclosed herein generally relate to a magnetic disk device employing a MAMR head. The MAMR head includes an STO. The STO comprises an underlayer, an SPL, an interlayer, an FGL, and a capping layer. The SPL is comprised of a high perpendicular magnetic anisotropy material. The SPL has a large effective perpendicular magnetic anisotropy field, and the SPL has a lower magnetic moment than the FGL. An applied current is adapted to flow in a direction from the FGL to the SPL resulting in the magnetization direction of the SPL being almost perpendicular to the FGL and anti-parallel to a head-gap magnetic field due to a relation between a first spin torque directed from the SPL to the FGL and a second spin torque directed from the FGL to the SPL.

Spin torque oscillator with low magnetic moment and high perpendicular magnetic anisotropy material

The present disclosure generally relates to a high-frequency oscillator for use in a recording device having a microwave-assisted magnetic recording head. The microwave-assisted magnetic recording head achieves a large assist effect by using an extended spin torque oscillator disposed between a main magnetic pole and a pole opposite the main magnetic pole. The spin torque oscillator obtains a strong high-frequency magnetic field and comprises a first non-magnetic spin scatterer, a reference layer, a first non-magnetic spin transfer layer, a first magnetic field generating layer, a second non-magnetic spin transfer layer, a second magnetic field generating layer, and a second non-magnetic spin scatterer. The spin torque oscillator has a drive current flowing though in the direction from the first magnetic field generating layer to the reference layer.

Extended spin torque oscillator

Embodiments disclosed herein generally relate to a MAMR head. The MAMR head includes an STO. The STO has a first magnetic layer, a second magnetic layer and an interlayer disposed between the first and second magnetic layers. One of the first and second magnetic layers is made of a negative polarization material while the other magnetic layer is made of a positive polarization material. As a result, the magnetizations in the first and second magnetic layers are in the same direction when in oscillation, which suppresses the partial cancellation of the magnetizations in the first and second magnetic layers and strengthens the AC magnetic field.

Negative-polarization spin-torque-oscillator

In one embodiment, a magnetic head includes a main magnetic pole positioned configured to generate a writing magnetic field when current is applied to a write coil, and a spin torque oscillator (STO) located adjacent the main magnetic pole, the STO being configured to generate a high frequency magnetic field when current is applied thereto, wherein the high frequency magnetic field is generated simultaneously to the writing magnetic field to assist in reversing magnetization of a magnetic recording medium. The STO includes: a spin polarization layer (SPL), a field generation layer (FGL) positioned adjacent the SPL, and one or more interlayers positioned between the SPL and the FGL, and a magnetization easy axis of the SPL is positioned in an in-plane direction such that the SPL has no perpendicular magnetic anisotropy.

Low Bs spin-polarizer for spin torque oscillator

In one embodiment, a magnetic head includes a main pole configured to write data to a magnetic medium, a trailing shield positioned on a trailing side of the main pole, and a STO between the main pole and the trailing shield, wherein the STO includes a laminated structure having a FGL, a spun polarization layer (SPL), and a non-magnetic spacer positioned between the FGL and the SPL, wherein the FGL includes a laminated structure having one or more layers of a CoFe alloy and a Heusler alloy alternately laminated in this order from an end of the FGL closest to the non-magnetic spacer. In another embodiment, a method is presented for forming such a magnetic head utilizing a FGL that includes a laminated structure baying layers of a CoFe alloy and a Heusler alloy alternately laminated in this order from an end of the FGL closest to the non-magnetic spacer.

Magnetic head having a spin torque oscillator (STO) with a hybrid heusler field generation layer (FGL)

In one embodiment, a spin torque oscillator (STO) includes a reference layer having a magnetization that is capable of free in-plane rotation, a field generation layer (FGL) including at least one magnetic film having an easy magnetization plane effectively in a film plane, wherein a magnetization of the FGL is capable of in-plane rotation, and a stabilizing layer (STL) positioned on a side of the FGL opposite the reference layer, the STL including a magnetic film having an easy magnetization plane effectively in a film plane, wherein a magnetization of the STL is capable of in-plane rotation, wherein a product of a saturation magnetization of the STL multiplied by a thickness of the STL is less than half a product of a magnetization of the FGL multiplied by a thickness of the FGL.

Stabilizing layer for a spin torque oscillator (STO)

A microwave-assisted magnetic recording (MAMR) head according to one embodiment includes a main pole; a trailing shield positioned downstream from the main pole; an oscillation device adapted to generate a high-frequency magnetic field, the oscillation device being positioned between the main pole and the trailing shield; a circuit adapted to flow an electric current therethrough to the main pole, the oscillation device, and the trailing shield; an electrically conductive non-magnetic body positioned on one or more sides of the main pole in a cross-track direction and/or a leading direction; and an insulating non-magnetic body positioned on one or more sides of the electrically conductive non-magnetic body in the cross-track direction and/or the leading direction, wherein one or more edge portions of one side of the oscillation device and one or more edge portions of one side of the main pole are in direct contact with the electrically conductive non-magnetic body.

MAMR head with a multi-layered side gap for stable oscillation of the STO

In one embodiment, a hard disk drive includes a magnetic disk medium, a magnetic head adapted for writing data to the magnetic disk medium, a mechanism (such as a detection circuit) adapted for detecting at least one recording condition of drive current provided to the magnetic head during writing operations, and an energy conversion element for controlling at least one recording characteristic of the magnetic head in response to the at least one detected recording condition. According to another embodiment, a method includes writing data to a magnetic medium using a magnetic head, detecting at least one recording condition of drive current provided to the magnetic head during the writing, and controlling at least one recording characteristic of the magnetic head during the writing using an energy conversion element in response to the at least one detected recording condition.

Growing community of inventors

Isehara, Japan

Keiichi Nagasaka