Seagate Technology Incorporated

Chunhong Hou

Lei Wang

Shaoping Li

Olle Gunnar Heinonen

Song Sheng Xue

Sining Mao

Qing I He

Xuefei Tang

Eric Walter Singleton

Mark Thomas Kief

Eric Shane Linville

John Wolf

Taras Grigoryevich Pokhil

Daniel John Brown

A writer includes a write element having a tip portion to generate a write field during a write operation and a conductive assembly that delivers a write assist current through the tip portion in a cross-track direction to generate a write assist field during the write operation that extends beyond a medium confronting surface located at the tip portion to lower a coercivity of a magnetic medium proximate to the write element.

Magnetic writer for field assisted magnetic recording

A perpendicular writer includes a surface, a main pole proximate the surface, a return pole proximate the surface, and a back yoke connecting the main pole to the return pole distal the surface. The return pole is configured such that a magnetization of a portion of the return pole adjacent the surface is held substantially parallel to the surface during a write operation.

Laminated return pole for suppressing side track erasure

A perpendicular writer includes a write coil and a main pole having a pole tip for conducting magnetic flux to write data to a magnetic medium. The pole tip includes a plurality of magnetic layers that are magnetically coupled and biased so that their magnetic moment orientations are substantially parallel to an external surface when no write current is applied to the write coil. The pole tip is partially embedded in the yoke, such that portions of the yoke surrounding the pole tip help direct magnetic flux to the pole tip. The pole tip extends beyond the yoke, with a first end located outside the yoke and a second end located within the yoke.

Layered perpendicular writer with pole tip partially embedded in yoke

A biasing system for a tri-layer reader stack magnetoresistive sensor is disclosed. The tri-layer reader stack includes a first ferromagnetic free layer, a second ferromagnetic free layer, and a magnetoresistive layer between the first and second ferromagnetic free layers. The free layers are positioned in the tri-layer reader stack such that quiescent state magnetizations of the free layers are antiparallel. A biasing layer is positioned with regard to the tri-layer reader stack, typically separated from the tri-layer reader stack by a nonmagnetic spacer layer. A biasing means is positioned such that a magnetization of the biasing layer is perpendicular to the quiescent state magnetizations of the free layers. This biasing results in the free layers having biased magnetizations directed substantially orthogonal with respect to each other.

Biasing for tri-layer magnetoresistive sensors

A structure for stabilizing the active region of the magnetic sensor comprises a hard ferromagnetic element adjacent to a biasing multilayer element placed on either side of the active region of the magnetic sensor. The biasing multilayer element includes soft ferromagnetic and anti-ferromagnetic layers such that the biasing strength applied to the active region of the magnetic sensor is tuneable by adjusting the length of the soft ferromagnetic layer or layers as well as the insertion of spacer layers between the soft ferromagnetic materials and the anti-ferromagnetic layers. The inventive structure provides longitudinal bias to the active region with improved domain control, signal amplitude and side-reading properties.

Mag-tab design for biasing magnetic sensors

A giant magnetoresistive stack for use in a magnetic read head has a plurality of layers including at least one ferromagnetic layer which contributes to a giant magnetoresistive signal, a doped ferromagnetic pinned layer and a doped ferromagnetic underlayer which do not contribute to a giant magnetoresistive signal. The dopant in the doped ferromagnetic pinned layer and underlayer reduces parasitic shunting current through the giant magnetoresistive stack by providing an increase in resistivity without a decrease in magnetization.

Giant magnetoresistive sensor with high-resistivity magnetic layers

A magnetoresistive stack for use in a magnetic read head has a plurality of layers including a ferromagnetic free layer, a ferromagnetic pinned layer, and an antiferromagnetic pinning layer. The pinned layer and pinning layer each have a greater number of structural grains than the free layer, which decreases a fluctuation of magnetization in the magnetoresistive stack without decreasing a spatial resolution of the magnetoresistive stack.

Growing community of inventors

Savage, MN, United States of America

Chunhong Hou