University of Minnesota

Seagate Technology Incorporated

Randall Harry Victora

Charles Frederick Brucker

Roy C Bell

Edward Charles Gage

Karl Arnold Belser

Ganping Ju

Jan-Ulrich Thiele

Terry Wayne McDaniel

Pin-Wei Huang

James E Durnin

Zengyuan Liu

Xi C Chen

An example article includes a composite free layer and a conductive channel. The composite free layer includes a high-anisotropy ferromagnetic layer, a non-magnetic transition metal layer adjacent to the high anisotropy ferromagnetic layer, and an ultra-low damping magnetic insulator. The non-magnetic transition metal layer is between the ultra-low damping magnetic insulator and the high-anisotropy ferromagnetic layer. An example spin-orbit torque (SOT) stack may include the example article. Techniques for forming and switching example articles and SOT stacks are described.

Spin-orbit torque devices

An example article includes a composite free layer and a conductive channel. The composite free layer includes a high-anisotropy ferromagnetic layer, a non-magnetic transition metal layer adjacent to the high-anisotropy ferromagnetic layer, and an ultra-low damping magnetic insulator. The non-magnetic transition metal layer is between the ultra-low damping magnetic insulator and the high-anisotropy ferromagnetic layer. An example spin-orbit torque (SOT) stack may include the example article. Techniques for forming and switching example articles and SOT stacks are described.

A heat-assisted magnetic recording media structure with exchange-coupled composite layer structure may be utilized in a data storage device. The heat-assisted magnetic recording disk structure can have a FePt-based layer as a storage layer and a FePt-based or a CoPt-based magnetic layer with higher Curie temperature as a write layer. The interface between the write layer and the storage layer may be separated by an exchange control layer. The composite structure can be optimized to reduce jitter for high density data storage by tuning the exchange coupling between the write layer and storage layer.

Composite HAMR media structure for high areal density

In general, the invention is directed to techniques for reducing the amount of switching current that is utilized within a magnetic storage (e.g., MRAM) device. An example apparatus includes a fixed magnetic layer that provides a fixed direction of magnetization, an exchange-coupled magnetic multi-layer structure, and a non-magnetic layer placed between the fixed magnetic layer and the exchange-coupled magnetic multi-layer structure. The exchange-coupled magnetic multi-layer structure includes a recording layer configured to record information and an assisting layer having a lower anisotropy than the recording layer. The exchange coupling between the recording and assisting layers is operable to switch a magnetization direction of the recording layer. In some cases, the exchange-coupled magnetic multi-layer structure may further include a spacer separating the recording and assisting layers and configured to weaken an exchange coupling between the recording and assisting layers.

Exchange-assisted spin transfer torque switching

Embodiments of a data storage system having thermally activated readout are provided, in one embodiment, a data storage system includes a source of heat, a substrate, a write layer disposed above the substrate, a copy layer disposed above the write layer, a flying head disposed above the layers and carrying the source of heat for heating a selected spot on the copy and write layers, wherein the write layer comprises a ferromagnetic material selected to have an extremely high coercivity at room temperature and a very high write temperature T, and the copy layer comprises a ferromagnetic material selected to have a coercivity always less than coercivity of the write layer at the same temperature and a copy temperature Tsubstantially less than the write temperature of the write layer.

Data storage system having thermally activated readout

The present invention relates to compensated crystalline superlattice ferrimagnets. The ferrimagnets include multiple ferromagnetic layers having different magnetic disordering temperatures in combination with antiferromagnetically coupled layers. The crystalline ferromagnetic layers may include metals or alloys such as Ni, Co and Fe. The crystalline antiferromagnetically coupled layers may include metals or alloys such as Rh, Ir, Cr, Ru, Os, W and Mn. The superlattice ferrimagnets may be used in such applications as data storage or memory layers in thermally assisted magnetic recording media.

Growing community of inventors

New Brighton, MN, United States of America

Randall Harry Victora