A head stack assembly for a hard disk drive includes a head gimbal assembly. The head gimbal assembly includes a slider, a plurality of microactuators, and a microactuator controller. The slider includes active components which are configured to perform drive operations in response to receiving control signals from a drive controller. The microactuators are configured to adjust the position of the slider relative to a magnetic disk during drive operations. The microactuator controller is configured to selectively couple the microactuators to a microactuator power source based on the control signals.

A head stack assembly for a hard disk drive includes a head gimbal assembly. The head gimbal assembly includes a slider, a plurality of microactuators, and a microactuator controller. The slider includes active components which are configured to perform drive operations in response to receiving control signals from a drive controller. The microactuators are configured to adjust the position of the slider relative to a magnetic disk during drive operations. The microactuator controller is configured to selectively couple the microactuators to a microactuator power source based on the control signals.

A disk drive apparatus determines a pattern of bits of a data signal applied to a magnetic write transducer of a heat-assisted magnetic recording apparatus. The magnetic write transducer applies a magnetic field to a recording medium in response to the data signal. A laser power signal is applied to a laser that heats the recording medium while the magnetic field is applied. The laser power signal is modulated based on the pattern of bits. The modulation reduces differences between track widths of recorded marks having different elapsed time values and/or increases a signal-to-noise ratio of the recorded marks having different elapsed time values.

A data storage drive includes a magnetic recording media comprising a ferroelectric layer between a bottom electrode layer and a top electrode layer. An applied voltage to the ferroelectric layer generates a strain that is transferred to a ferromagnetic recording layer formed proximate to the ferroelectric layer. The change in strain transferred to the recording layer changes the magnetic properties of the recording layer. A voltage can be selectively applied to all or part of the ferroelectric layer to place the ferromagnetic recording layer in a low coercivity state to assist in writing data. Voltage-assisted magnetic recording (VAMR) is provided based upon control of a magnetic recording media comprising a ferroelectric layer between a bottom electrode layer and a top electrode layer.

An apparatus, according to one embodiment, includes a substrate and a closure above the substrate. A gap is positioned between the closure and the substrate, the gap having an array of magnetic transducers extending therealong and unpatterned films. The gap further includes a first layer of a first material having a bulk modulus of elasticity lower than the unpatterned films in the gap. An apparatus according to another embodiment includes a plurality of magnetic transducers arranged in a linear array, and a layer of an expansion material between each adjacent pair of magnetic transducers in the array. An encapsulant is positioned between each layer of the expansion material and the adjacent magnetic transducers. The expansion material has a greater coefficient of thermal expansion than the encapsulant.

According to one embodiment, a magnetic disk device includes: a disk; a head including a main magnetic pole, a write shield that faces the main magnetic pole in a first direction and is separated from the main magnetic pole by a gap, a first assist element that is disposed in the gap and a second assist element that is disposed in the gap and is positioned relative to the first assist element in a second direction intersecting the first direction; and a controller configured to: cause a first assist energy from the first assist element to be applied to the disk and affect a coercive force of the disk; and cause a second assist energy from the second assist element to be applied to the disk and affect a coercive force of the disk, wherein the first assist energy is different from the second assist energy.

Two or more different elapsed time values are determined between transitions of a data signal applied to a magnetic write transducer of a heat-assisted magnetic recording apparatus. Two or more different power values of the laser are respectively associated with the two or more different elapsed time values. The two or more different power levels are selected to reduce differences between track widths of recorded marks having the two or more different elapsed time values.

According to one embodiment, a magnetic disk device includes a magnetic head, a magnetic disk on which a servo pattern used to position the magnetic head when data is to be recorded by means of the magnetic head is recorded, and a control section configured to set a recording condition for each predetermined unit of the magnetic disk on the basis of the servo pattern, and carry out recording of data on the magnetic disk according to the set recording condition.

According to one embodiment, a magnetic disk device includes: a disk; a head including a main magnetic pole, a write shield that faces the main magnetic pole in a first direction and is separated from the main magnetic pole by a gap, a first assist element that is disposed in the gap and a second assist element that is disposed in the gap and is positioned relative to the first assist element in a second direction intersecting the first direction; and a controller configured to: cause a first assist energy from the first assist element to be applied to the disk and affect a coercive force of the disk; and cause a second assist energy from the second assist element to be applied to the disk and affect a coercive force of the disk, wherein the first assist energy is different from the second assist energy.

A hard disk drive includes an enclosure housing a first set of magnetic recording media coupled to a first spindle motor, a second set of magnetic recording media coupled to a second spindle motor, and a third set of magnetic recording media coupled to a third spindle motor. The first set of magnetic recording media at least partially overlaps with the second set of magnetic recording media and the third set of magnetic recording media.