Seagate Technology Incorporated

Robert William Lamberton

Mark Anthony Gubbins

James Joseph Touchton

Robert Edward Weinstein

William J O'Kane

Zhiran Wang

Kaizhong Gao

Declan Macken

Kevin Anthony McNeill

Dimitar Velikov Dimitrov

Haiwen Xi

Wenzhong Zhu

Michael L Mallary

Insik Jin

Huaqing Yin

Jianhua Xue

Dadi Setiadi

Eric Shane Linville

Thomas Roy Boonstra

Marcus Winston Ormston

Swaraj Basu

Eric Roger Meloche

Johannes Van Ek

Muhammad Asif Bashir

Xuefei Tang

Sameh Hassan

Alexandru Cazacu

Xin Cao

Ge Yi

Alexey Dobrynin

Frank A McGinnity

Denis O'Donnell

Alex Wong

Paul M Dodd

Susan Jane Tara Murdoch

Thomas K McLaughlin

Alex Yu Loong Wong

The presently disclosed technology teaches integrating disc drive electronics into a transducer head. Decreased electrical transit times and data processing times can be achieved by placing the electronics on or within the transducer head because electrical connections may be made physically shorter than in conventional systems. The electronics may include one or more of a control system circuit, a write driver, and/or a data buffer. The control system circuit generates a modified clock signal that has a fixed relation to phase and frequency of a bit-detected reference signal that corresponds to positions of patterned bits on the disc. The write driver writes outgoing data bits received from an external connection to off-head electronics directly to the writer synchronized with the modified clock signal. The data buffer stores and converts digital data bits sent from the off-head electronics to an analog signal that is synchronized with the modified clock signal.

On head microelectronics for write synchronization

A read sensor having a bearing surface and an antiferromagnetic (AFM) layer recessed from the bearing surface. The read sensor includes a synthetic antiferromagnetic (SAF) structure over the AFM layer. The SAF structure includes a recessed lower pinned layer, an upper pinned layer, a reference layer and a stabilization feature. The stabilization feature may include deliberate reduction of the antiferromagnetic coupling energy density between the upper pinned layer and the reference layer, so that it becomes lower than the first energy density of antiferromagnetic coupling between the upper pinned layer and the lower pinned layer. The stabilization feature may alternatively include an intermediate pinned layer between the lower pinned layer and the upper pinned layer. The intermediate pinned layer is antiferromagnetically coupled to both the lower pinned layer and the upper pinned layer, and at least a portion of the intermediate pinned layer is recessed behind the bearing surface.

Magnetoresistive sensor with recessed antiferromagnetic layer and stabilization feature

A data reader may have a magnetoresistive stack positioned on an air bearing surface and consisting of at least a magnetically free structure that continuously extends from the air bearing surface with a first stripe height. A side shield can be separated from the magnetoresistive stack on the ABS and configured with a first magnetic layer having the first stripe height and a second magnetic layer having a third stripe height from the air bearing surface with the third stripe height being greater than the first stripe height. The side shield can be anti-ferromagnetically biased by a synthetic antiferromagnetic top shield structure that contacts the side shield through a transition metal material layer. The first stripe height can be configured to match a magnetically free layer of the magnetoresistive stack and the second stripe height can be configured to match a magnetically fixed layer of the magnetoresistive stack.

Data reader side shield with differing stripe heights

An apparatus may be constructed with a magnetic element, such as a data transducing head. A first permanent magnet may be configured to bias the write pole to decrease remnant magnetization and erasure after write (EAW). The first permanent magnet can be separated from the write pole be a predetermined distance.

Magnetically biased write pole

The application discloses pole tip shield assemblies for a magnetic write element. The shield assemblies disclosed include side shields to limit adjacent track interference. The side shields are truncated or notched at a midpoint to form an expanded non-magnetic gap along a trailing portion of the pole tip to enhance write field and/or field gradient. The expanded non-magnetic gap region is larger than the non-magnetic gap region along a leading portion of the pole tip.

Pole tip shield for a magnetic write element having notched or truncated side shields

Method and apparatus for writing data to a magnetic memory element, such as a spin-torque transfer random access memory (STRAM) memory cell. In accordance with various embodiments, a write current is applied through a magnetic memory element to initiate magnetic precession of the element to a desired magnetic state. A flow of a field assist current is subsequently initiated adjacent the magnetic memory element during continued application of the write current to induce a magnetic field upon the element. The field assist current persists after the write current is terminated to provide field assisted precession to the desired magnetic state.

Field assisted switching of a magnetic memory element

Methods and devices are provided for microwave-assisted magnetic recording with collocated microwave and write fields. An illustrative device includes a magnetic write pole and one or more alternating-field components. The magnetic write pole is configured for providing a magnetic write field. The one or more alternating-field components are disposed to at least partially coincide with the magnetic write pole. The one or more alternating-field components are configured to provide an alternating magnetic field having a microwave frequency and an orientation that is at least partially transverse to the magnetic write field.

Microwave-assisted magnetic recording with collocated microwave and write fields

A non-limiting embodiment of a magnetic writer has at least a write element having a write element tip and a conductive structure adjacent the write element. The conductive structure has at least two conductive elements positioned substantially parallel to one another and separated by an electrically insulating material. Each of the conductive elements carries a time-varying signal to generate an oscillating magnetic field from a displacement current between the two conductive elements, with the oscillating magnetic field being proximate the write element tip and extending parallel to the air bearing surface. A frequency of the oscillating magnetic field is a function of a frequency of the time-varying signal.

Transducing head design for microwave assisted magnetic recording

A method and apparatus for managing data, particularly in regard to non-volatile memory cells. In some embodiments, at least two actuating conductors are at least partially surrounded by a main ferromagnetic core and an adjacent hard magnet. When current is conducted through the actuating conductors, a flexible beam is induced to traverse a first air gap that defines a high resistance position and a low resistance position.

Magnetic mechanical switch

The present invention includes magnetic write elements with portions formed a nanophase high magnetic moment material to enable further increases in areal density in magnetic recording. The nanophase deposited high magnetic moment material comprises coated nanoclusters and nanolaminated cluster films that are deposited to form nanophase high magnetic moment material portions of a write pole and SUL layer in perpendicular recording media. The nanophase write poles exhibit high magnetic moments and are generally compatible with conventional writer head fabrication techniques.

Nanoclustered magnetic materials for high moment write pole applications

A spin polarization enhancement artificial (SPEA) magnet comprises combinations of positive spin asymmetry interfaces and inverse spin asymmetry interfaces arranged antiferromagnetically such that current passed through the SPEA magnet has enhanced spin polarization. The SPEA magnet additionally may combine bulk material properties of electron scattering to either supplement or replace the interfacial spin differentiation. A basic functional unit of the SPEA magnet includes two ferromagnetic layers separated by two spacer layers. Each spacer forms an interface such that adjacent ferromagnetic layers produce different spin symmetry. Antiferromagnetic arrangement of adjacent ferromagnetic layers coordinates the different spin symmetries such that a single spin state is selected and also provides additional stabilization to the SPEA magnet.

Spin polarization enhancement artificial magnet

Growing community of inventors

Limavady, Ireland

Robert William Lamberton