Aspects of the disclosure provide for mitigating a coefficient of thermal expansion (CTE) mismatch between glass components and adjacent metal components in a disk storage device to improve thermal and shock performance. The methods and apparatus provide a hub, provide a first recording disk comprising a glass material and a center hole on the hub such that the hub extends through the center hole of the first recording disk, provide a first spacer on the first recording disk, the first spacer comprising a nickel-iron alloy, and provide a second recording disk comprising a glass material and a center hole on the first spacer such that the hub extends through the center hole of the second recording disk, wherein the first recording disk and the second recording disk each comprise a magnetic recording layer configured to store information.

A server box embodiment is disclosed that generally comprises an array of dummy HDDs that share a common set of universal disk drive components in a master components module, or power module. Each dummy HDDs is constructed without expensive onboard chipsets that control the normal functionality of a standard HDD. By sharing expensive chipsets in a master components module (power module) money can be saved in building and selling the dummy HDD server. Embodiments envision a power module possessing the needed chipset functionality that is missing in a dummy HDD. The power module can be made to move from dummy HDD to dummy HDD supplying the necessary chipset in a shared manner when data is being stored or retrieved for client or end-user.

A control system for fully automatic turntables is revealed. The control system includes a receiver module therein for receiving signals from application programs to activate a drive source and a control assembly which control a platter and a tonearm respectively. The control assembly includes a first rod provided with an upper rack and a second rod provided with a lower rack. The first and second rods are inserted and installed on a base. A power source disposed on the base is for driving a first gear set correspondingly and a connecting rod is also moved to drive a second gear set. Thus partial gears of the first and second gear sets are engaged with the upper and lower racks alternately. The first and second rods are further driven to move or stop the tonearm respectively. Therefore, automatic movement of the tonearm is achieved.

A control system for fully automatic turntables is revealed. The control system includes a receiver module therein for receiving signals from application programs to activate a drive source and a control assembly which control a platter and a tonearm respectively. The control assembly includes a first rod provided with an upper rack and a second rod provided with a lower rack. The first and second rods are inserted and installed on a base. A power source disposed on the base is for driving a first gear set correspondingly and a connecting rod is also moved to drive a second gear set. Thus partial gears of the first and second gear sets are engaged with the upper and lower racks alternately. The first and second rods are further driven to move or stop the tonearm respectively. Therefore, automatic movement of the tonearm is achieved.

A magnetic tunneling junction (MTJ) structure is described. The MJT structure includes a stress modulating layer on a first electrode layer, where a material of the stress modulating layer is different from a material of the first electrode layer. The MJT structure further includes a MTJ material stack on the stress modulating layer. And the MJT structure further includes a second electrode layer on the MTJ material stack. The stress modulating layer reduces crystal growth defects and interfacial defects during annealing and improve the interface lattice epitaxy. This will improve device performance.

According to one embodiment, a disk device includes a plurality of recording media each including a recording layer and an actuator assembly including an actuator block rotatably supported around a rotation shaft, a plurality of arms extending from the actuator block, and suspension assemblies respectively attached to the arms and supporting respective magnetic heads. Of the plurality of arms, at least one arm has vibration characteristics different from those of the other arms.

According to an embodiment, a magnetic disk device includes a magnetic disk, a spindle motor that rotates the magnetic disk, a motor driver, and a controller. The motor driver supplies a motor current to the spindle motor and measures a counter electromotive voltage of the spindle motor every time the spindle motor makes one rotation. After the rotation of the magnetic disk starts, the controller adjusts a motor position where the counter electromotive voltage is measured to a set first position.

A removable disk clamp assembly for mounting disk media on a motor-driven spindle of a magnetic read-write device includes a disk clamp and a mechanism for generating a predetermined force to press the disk media to a flange of the spindle such that the predetermined force can be repeatedly overcome by an applied counterforce to remove the disk clamp from engagement with a hub of the spindle. Such a mechanism may include a spring-loaded removable disk clamp assembly or a magnetic removable disk clamp assembly, and whereby a vacuum-driven chuck may be employed for disk and clamp handling purposes, all of which are suitable for implementation and use in a read-write device configured for use in an archival data storage system library such as in a cleanroom storage system.

A disk hub is configured to retain a magnetic recording medium including an annulus shape and a layer configured for magnetic recording. The disk hub includes a base plate portion for supporting an inner diameter area of the magnetic recording medium and a stem portion on the base plate portion. The stem portion includes a frustoconical portion on the base plate portion and a top portion on the frustoconical portion. At least the top portion of the stem portion includes a material with a hardness less than that of stainless steel. The disk hub can reduce surface damages (e.g., scratches) on the media surface during media testing.

A magnetic tunneling junction (MTJ) structure is described. The MJT structure includes a stress modulating layer on a first electrode layer, where a material of the stress modulating layer is different from a material of the first electrode layer. The MJT structure further includes a MTJ material stack on the stress modulating layer. And the MJT structure further includes a second electrode layer on the MTJ material stack. The stress modulating layer reduces crystal growth defects and interfacial defects during annealing and improve the interface lattice epitaxy. This will improve device performance.