Western Digital Technologies, Inc.

Tokyo Institute of Technology

Institute of Science Tokyo

Nam Hai Pham

Quang Le

Cherngye Hwang

Xiaoyong Liu

Hisashi Takano

Brian Rodrick York

Son T Le

Hassan Osman

Fan Tuo

Huy H Ho

Kuok San Ho

Tsuyoshi Kondo

Michael Gribelyuk

Maki Maeda

Xiaoyu Xu

Rohan Babu Nagabhirava

Sharon Swee Ling Banh

Huynh Duy Khang Nguyen

Khang H D Nguyen

Julian Sasaki

Takanori Shirakura

Takanori Shirokura

Yu Tao

The present disclosure generally relates to temperature detection devices including a ferromagnetic (FM) material disposed at a media facing surface (MFS). The FM material is configured to produce a first electric voltage signal in response to a temperature gradient due to an anomalous Nernst effect. The temperature detection device may also include a spin-orbit torque (SOT) material abutting the FM material. The SOT material includes at least one of BiSb, a topological insulator, a topological half-Heusler alloy, or a weakly oxidized heavy metal. The SOT material is recessed from the MFS, wherein the SOT material is configured to receive a spin current parallel to the temperature gradient generated by a spin Seebeck effect in the FM material. The spin current is detectable as a second electric voltage signal via an inverse spin Hall effect. The first electric voltage signal is added to the second electric voltage signal.

Spin orbit torque based thermal sensor for insitu monitoring of magnetic recording head

The present disclosure generally relates to a magnetic recording head comprising a read head. The read head comprises a first sensor disposed at a media facing surface (MFS) comprising at least one free layer, a second sensor disposed at the MFS comprising at least one free layer, a first spin generator spaced from the first sensor and recessed from the MFS, and a second spin generator spaced from the second sensor and recessed from the MFS. The first and second spin generators each individually comprises at least one spin orbit torque (SOT) layer. The SOT layer may comprise BiSb. The first and second sensors are configured to detect a read signal using a first voltage lead and a second voltage lead. The first and second spin generators are configured to inject spin current through non-magnetic layers to the first and second sensors using a plurality of current leads.

Non-localized spin valve multi-free-layer reader hybridized with spin orbit torque layers

The present disclosure generally relates to a magnetic recording head comprising a read head. The read head comprises a sensor disposed at a media facing surface (MFS) and a spin generator spaced from the sensor and recessed from the MFS. The sensor and spin generators are disposed on a non-magnetic layer. The sensor comprises a free layer and the spin generator comprises at least one spin orbit torque (SOT) layer. The SOT layer may comprise topological material such as BiSb. The sensor is configured to detect a read signal using a first voltage lead and a second voltage lead. The spin generator is configured to inject spin current through the non-magnetic layer to the sensor using a first current lead and a second current lead. The shape of the non-magnetic layer is a triangular or trapezoidal shape to further concentrate spin current.

Non-localized spin valve reader hybridized with spin orbit torque layer

The present disclosure generally relates to a magnetic media drive comprising a magnetic recording head. The magnetic recording head comprises a main pole disposed at a media facing surface (MFS), a shield disposed at the MFS, a spin blocking layer disposed between the shield and the main pole, at least one non-magnetic layer disposed between the main pole and the shield, the at least one non-magnetic layer being disposed at the MFS, and at least one spin orbit torque (SOT) layer disposed over the at least one non-magnetic layer, the SOT layer being recessed a distance of about 20 nm to about 100 nm from the MFS. A ratio of a length of the SOT layer to a thickness of the SOT layer is greater than 1. The at least one SOT layer comprises BiSb.

Higher areal density non-local spin orbit torque (SOT) writer with topological insulator materials

According to one embodiment, a spin injection source comprising a half Heusler alloy-topological semi-metal that has a surface state of Dirac type and that is in contact with a ferromagnet. The half Heusler alloy-topological semi-metal supplies a spin current to the ferromagnet based on a current flowing in a direction parallel to a first surface that is in contact with the ferromagnet.

Spin injection source, magnetic memory, spin hall oscillator, computer, and magnetic sensor

The present disclosure generally relates to a magnetic recording head comprising a spintronic device for magnetic media, such as a magnetic media drive. The spintronic device includes at least one spin Hall layer as well as at least one buffer layer and at least one interlayer. The buffer layer is positioned proximate a main pole of a write head while the interlayer is positioned proximate a trailing shield of the write head. The spin Hall layer is positioned between the buffer layer and the interlayer. The spintronic element may be disposed at the media facing surface (MFS) or recessed from the MFS. The spintronic device is capable of injecting spin current to the main pole, the trailing shield, or both.

Spin-orbit torque (SOT) writer with topological insulator materials

An oscillator includes a spin current source, and a free layer coupled to the spin current source. The free layer has a magnetization hard axis that is parallel to a quantization axis of a spin current injected by the spin Hall effect of the spin current source.

Spin hall oscillator

The present disclosure generally relate to spin-orbit torque (SOT) devices. The SOT devices each comprise a non-magnetic layer, a free layer disposed in contact with the non-magnetic layer, and a bismuth antimony (BiSb) layer disposed over the free layer. The non-magnetic layer has a thickness of about 0.5 nm to about 2 nm. The BiSb layer has a thickness of about 5 nm to about 10 nm. The BiSb layer and the free layer have collective thickness between about 5 nm to about 20 nm. By reducing the thickness of the non-magnetic layer and BiSb layer, a read gap of each SOT device is reduced while enabling large inverse spin Hall angles and high signal-to-noise ratios.

SOT reader using BiSb topological insulator

A magnetoresistive memory cell includes an MTJ element including a magnetization free layer and a pure spin injection source. The pure spin injection source includes a BiSb layer coupled to the magnetization free layer. By flowing an in-plane current through the BiSb layer, this arrangement is capable of providing magnetization reversal of the magnetization free layer.

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Tokyo, Japan

Nam Hai Pham