Seagate Technology Incorporated

Hgst Netherlands, B.v.

Western Digital Technologies, Inc.

The Bank of Nova Scotia, As Administrative Agent

Hans Juergen Richter

Samuel Dacke Harkness, Iv

Erhard Theodor Schreck

Barry C Stipe

Dieter Klaus Weller

Michael Grobis

Erol Girt

Oleksandr Mosendz

Alexander Yulievich Dobin

Thomas P Nolan

Samuel Dacke Harkness

Zhong (Stella) Wu

Roger K Malmh&auml;ll

Edward Charles Gage

Petrus Antonius Van Der Heijden

Lidu Huang

Qing Dai

Olav Hellwig

Youfeng Zheng

Mark H Kryder

Andreas Moser

Terry Wayne McDaniel

Shen Ren

Matteo Staffaroni

Rene Johannes Marinus Van De Veerdonk

Robert E Eaton

Li Tang

Gary Clark Rauch

Simone Pisana

Franck Rose

James William Reiner

Gregory John Parker

Shikha Jain

Richard Michael Brockie

Yong-Chang Feng

Provided herein is an apparatus, including a magnetically soft underlayer (SUL); an interlayer stack overlying the SUL, wherein the interlayer stack comprises a seed layer of an fcc material; and a perpendicular magnetic recording layer overlying the interlayer stack, wherein a thickness of the SUL in combination with a distance of the SUL from the perpendicular recording layer is sufficient to orient a total magnetic field corresponding to a magnetic transducer head at an angle of about 45&#xb0;.

Apparatus comprising magnetically soft underlayer

A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a laser configured to heat the disk while writing data to the disk. At least four different laser powers are applied to the laser and a fly height of the head over the disk is measured at each laser power. A lasing threshold power for the laser is detected based on the measured fly heights.

Data storage device detecting lasing threshold of laser by measuring protrusion effect

An apparatus may include a first magnetic layer, a first exchange break layer formed on the first magnetic layer, a second magnetic layer formed on the first exchange break layer, a second exchange break layer formed on the second magnetic layer, and a third magnetic layer formed on the second exchange break layer. The first magnetic layer has a first magnetic anisotropy energy, H, the second magnetic layer has a second magnetic anisotropy energy, H, and the third magnetic layer has a third magnetic anisotropy energy, H. In some embodiments, H&#x2212;His less than H&#x2212;H. In some embodiments, the apparatus may be a perpendicular magnetic recording medium.

Apparatus including a perpendicular magnetic recording layer having a convex magnetic anisotropy profile

According to one embodiment, a magnetic recording medium includes: a substrate, a seed layer positioned above the substrate, and a magnetic recording layer structure positioned above the seed layer. The magnetic recording layer structure includes: a first magnetic recording layer having a plurality of FePtCu magnetic grains and a first segregant, and a second magnetic recording layer positioned above the first magnetic recording layer, the second magnetic recording layer having a plurality of FePt magnetic grains and a second segregant, where a Curie temperature of the first magnetic recording layer is lower than a Curie temperature of the second magnetic recording layer.

Heat assisted magnetic recording (HAMR) media having a highly ordered crystalline structure

A method for etching a media is disclosed. A first magnetic layer comprising grains is deposited with a segregant such that a portion of the first segregant covers a top surface of the grains of the first magnetic layer and a second portion of the first segregant separates the grains of the first magnetic layer. The first segregant is etched to remove the portion of the first segregant that covers the top surface of the grains.

Media etch process

In one general embodiment, an apparatus includes a write pole, a near field transducer, a waveguide for delivering light to the near field transducer, and a first heating device positioned between the write pole and at least one of the waveguide and the near field transducer.

Combined micro heater and waveguide power sensor for heat-assisted magnetic recording

A quantum dot (QD) sensitized wide bandgap (WBG) semiconductor heterojunction photovoltaic (PV) device comprises an electron conductive layer; an active photovoltaic (PV) layer adjacent the electron conductive layer; a hole conductive layer adjacent the active PV layer; and an electrode layer adjacent the hole conductive layer. The active PV layer comprises a wide bandgap (WBG) semiconductor material with E&#x2267;2.0 eV, in the form of a 2-dimensional matrix defining at least two open spaces, and a narrower bandgap semiconductor material with E&#x3c;2.0 eV, in the form of quantum dots (QD's) filling each open space defined by the matrix of WBG semiconductor material and establishing a heterojunction therewith. The active PV layer is preferably fabricated by a co-sputter deposition process, and the QD's constitute from about 40 to about 90 vol. % of the active PV layer.

Quantum dot-sensitized wide bandgap semiconductor heterojunction photovoltaic devices

Storage architecture for bit patterned media uses both erase band and shingled magnetic recording. A hard disk drive may comprise a disk having bit patterned media with a plurality of data tracks arrayed in architecture pages having at least one of erase band mode (EBM), shingled mode (SM) and unallocated space. An actuator has a head for writing data to the data tracks of the bit patterned media. A control system monitors, reallocates and reconfigures the architecture pages from EBM, SM or unallocated space to a different one of EBM, SM or unallocated space to enhance performance of the hard disk drive.

System, method and apparatus for storage architecture for bit patterned media using both erase band and shingled magnetic recording

A bit patterned magnetic recording medium, comprises a non-magnetic substrate having a surface; a plurality of spaced apart magnetic elements on the surface, each of the elements constituting a discrete magnetic domain or bit; and a layer of a ferromagnetic material for regulating magnetic exchange coupling between said magnetic elements. The layer has a saturation magnetization Mranging from about 1 to about 2,000 emu/cm, preferably below about 400 emu/cm, more preferably below about 200 emu/cm, and may overlie, underlie, or at least partially fill spaces between adjacent magnetic elements.

Bit patterned magnetic media

The present invention generally relates to a magnetic recording system that utilizes perpendicular exchange spring media and ring heads. The write field of ring heads does not experience a strong loss as compared to pole heads because the pole can be kept long in the direction perpendicular to the recording medium and thus does not result in unfavorable write field scaling.

Magnetic recording system using perpendicular exchange spring media and ring heads

A thermally-assisted recording (TAR) disk drive operates by turning on write current prior to the application of heat to the recording layer by the near-field transducer (NFT). In a TAR disk drive that uses thermal fly-height control (TFC), TFC power is at a first power level that keeps the write pole at a predetermined fly-height. The write current is then turned on, either simultaneously with or after a reduction in TFC power. The write pole then reaches its optimal fly-height as a result of the combination of write pole protrusion caused by the write current and retraction of the write pole caused by the reduction in TFC power. After the write pole has reached its optimal fly-height, heat is applied to the recording layer by the NFT. The combination of write current and heat causes writing to occur at the optimal write pole fly-height.

Method for controlling writing in a thermally-assisted recording (TAR) disk drive with thermal fly-height control

A bit patterned magnetic recording medium comprises a substrate having a surface, and a plurality of spaced apart magnetic elements on the surface, each element constituting a discrete magnetic domain or bit of the same structure and comprised of a stack of thin film layers including in order from the substrate surface: a seed layer; and a perpendicular magnetic recording layer in contact with a surface of the seed layer and comprising a CoPtCralloy material, where 0.05&#x2266;x&#x2266;0.35 and 0&#x2266;y&#x2266;0.15. The CoPtCralloy material has a first order magnetic anisotropy constant Kup to about 2&#xd7;10erg/cm, a saturation magnetization Mup to about 1200 emu/cm, an anisotropy field H=2K/Mup to about 35 kOe, a hexagonal () crystal structure with c-axis perpendicular to a surface thereof, and an X-Ray diffraction (XRD) rocking curve with a full width at half maximum (FWHM) of &#x2dc;5&#xb0; or less.

CoPtCr-based bit patterned magnetic media

A heat enabled magnetic media having a composite magnetic recording layer structure that includes first and second magnetic layers and an exchange coupling layer sandwiched between the first and second magnetic layers. The exchange coupling layer has a reduced Curie temperature that allows the magnetic layers to become decoupled a lower temperature. This reduced Curie temperature can be achieved the addition of an alloying element such as Ni or Cu into the exchange coupling layer. Therefore, the exchange coupling layer can be constructed of an alloy such as FePtNi FePtCu, and the magnetic layers can be constructed of a material such as FePt.

Thermally enabled exchange coupled media for magnetic data recording

Instead of using discontinuous step functions or pulses to drive a laser of a TAR enabled disk drive between on and off, a fixed modulation frequency may be used that alternates between a high and low laser power such that the radiation source is always delivering heat to the magnetic media when writing data to the magnetic disk. The magnetic field of the write pole may be synchronized to the modulation frequency of the radiation source to ensure that the radiation source heats the magnetic media proximate to the write pole above the grain freezing temperature when the Zeeman energy produced by the magnetic field of the write pole exceeds the thermal energy of the magnetic media.

Growing community of inventors

Palo Alto, CA, United States of America

Hans Juergen Richter