A voice coil motor yoke having a magnet bonding surface includes an annular groove inside a bonding region on the magnet bonding surface, the bonding region having substantially the same shape as a contour of a magnet to be bonded on the magnet bonding surface of the yoke. A region surrounded by the annular groove on the magnet bonding surface is an adhesive application region. A voice coil motor includes: a pair of the voice coil motor yokes; an adhesive applied to the adhesive application region of each of the pair of yokes; and a pair of rare earth magnets bonded via the adhesive to the bonding region of each of the pair of yokes.

Example systems, data storage devices, and methods to provide long-term spacing compensation for heat assisted magnetic recording are described. The data storage device includes a storage medium with data tracks and a head that can be positioned for reading and writing those tracks. The head includes a laser for heat assisted magnetic recording and a fly height actuator. Based on the operation of the laser, both a short-term fly height compensation parameter and a long-term fly height compensation parameter are determined based on different temperature state models. The operating power of the fly height actuator is determined, at least in part, based on the short-term and long-term height compensation parameters.

Example systems, data storage devices, and methods to provide long-term spacing compensation for heat assisted magnetic recording are described. The data storage device includes a storage medium with data tracks and a head that can be positioned for reading and writing those tracks. The head includes a laser for heat assisted magnetic recording and a fly height actuator. Based on the operation of the laser, both a short-term fly height compensation parameter and a long-term fly height compensation parameter are determined based on different temperature state models. The operating power of the fly height actuator is determined, at least in part, based on the short-term and long-term height compensation parameters.

Various illustrative aspects are directed to a data storage device, comprising: one or more disks; an actuating mechanism comprising one or more heads, and configured to position the one or more heads proximate to disk surfaces of the one or more disks; and one or more processing devices. The one or more processing devices are configured to: determine a first burst value based on an averaged value of a first set of one or more bursts; determine a second burst value based on an averaged value of a second set of one or more bursts; generate a position error signal (PES) based on the determined first burst value and the determined second burst value; and control a position of at least one head among the one or more heads based on the PES.

Various illustrative aspects are directed to a data storage device, comprising: one or more disks; an actuating mechanism comprising one or more heads, and configured to position the one or more heads proximate to disk surfaces of the one or more disks; and one or more processing devices. The one or more processing devices are configured to: determine a first burst value based on an averaged value of a first set of one or more bursts; determine a second burst value based on an averaged value of a second set of one or more bursts; generate a position error signal (PES) based on the determined first burst value and the determined second burst value; and control a position of at least one head among the one or more heads based on the PES.

According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a heater a control section. When making the magnetic head carry out the seek operation from the first position to the second position, the control section starts application of a first voltage to the heater while the seek operation is carried out and, after application of the first voltage, makes the voltage to be applied to the heater a second voltage greater than the first voltage before the magnetic head is positioned to the second position and write of data is started by the magnetic head.

According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a heater a control section. When making the magnetic head carry out the seek operation from the first position to the second position, the control section starts application of a first voltage to the heater while the seek operation is carried out and, after application of the first voltage, makes the voltage to be applied to the heater a second voltage greater than the first voltage before the magnetic head is positioned to the second position and write of data is started by the magnetic head.

A storage apparatus includes a disk-shaped recording medium, a motor configured to drive and rotate the recording medium, a head configured to read information from and write information to the recording medium, and a support member configured to support the recording medium when the recording bends in response to external vibration or shock. The support member supports the recording medium by making contact with the recording medium only when the external vibration or shock is applied to the storage apparatus.

A storage apparatus includes a disk-shaped recording medium, a motor configured to drive and rotate the recording medium, a head configured to read information from and write information to the recording medium, and a support member configured to support the recording medium when the recording bends in response to external vibration or shock. The support member supports the recording medium by making contact with the recording medium only when the external vibration or shock is applied to the storage apparatus.

A method includes determining at least one of an areal density margin or a reliability margin for a combination of a head and a data storage surface in a data storage drive. The method also includes employing the determined at least one of the AD margin or the reliability margin to adjust an on-cylinder limit value associated with the combination of the head and the data storage surface.