An apparatus comprises a slider configured to facilitate heat assisted magnetic recording and a submount affixed to the slider. A laser unit is affixed to the submount and comprises a laser operable in a non-lasing state and a lasing state. A heater is embedded in the laser unit or the submount. The heater is configured to generate preheat for heating the laser during the non-lasing state and to generate steering heat for heating the laser during the lasing state.

A method of assembly a dual stage actuated suspension includes either applying an adhesive to a microactuator motor and then B-staging the adhesive, or applying an adhesive that has already been B-staged such as in film adhesive form to the microactuator then assembling the microactuator into a suspension and then finishing the adhesive cure. The adhesive can be applied to bulk piezoelectric material, with the adhesive being B-staged either before or after it is applied to the bulk piezoelectric material, and the piezoelectric material then singulated into a number of individual piezoelectric microactuators. The method allows greater control over how much adhesive is used, and greater control over spread of that adhesive and control over potential contamination, than traditional liquid epoxy dispense methods.

A magnetic recording medium includes a recording surface comprising a first recording layer having a first ferromagnetic resonant frequency and a second recording layer having a second ferromagnetic resonant frequency. The first recording layer is configured for storing user data and the second recording layer configured for storing servo data. A recording head arrangement is configured for microwave-assisted magnetic recording (MAMR) and writing user data to the first recording layer. The recording head arrangement comprises a write pole configured to generate a write magnetic field, and a write-assist arrangement proximate the write pole. The write-assist arrangement is configured to generate a radiofrequency assist magnetic field at a frequency that corresponds to the first ferromagnetic resonant frequency. A reader of the recording head arrangement is configured to read combined signals from the first and second recording layers.

According to one embodiment, a magnetic recording head includes a main magnetic pole which applies a recording magnetic field to a magnetic recording medium, an auxiliary magnetic pole which faces the main magnetic pole across a recording gap, a first magnetic bypass layer which is provided in a recording gap in a track direction, and a second magnetic bypass layer which is provided in the recording gap in the track direction and is arranged at a distance from the first magnetic bypass layer in a track width direction.

The present disclosure describes aspects of pulse-based writing for magnetic storage media. In some aspects, a pulse-based writer of magnetic storage media determines that a string of data bits having a same polarity corresponds to a magnet longer than a threshold associated with a magnetic media writer. The pulse-based writer inserts, into the string of data bits, a transition to a polarity opposite to the same polarity of the string of data bits. The string of data bits including the inserted transition is then transmitted to the magnetic media writer to cause a write head of the writer to pulse while writing the magnet to magnetic storage media. Various aspects may also implement a control signal to mask a transition or control polarity of the magnetic media writer. By so doing, magnets may be written to the magnetic storage media more efficiently or with less distortion to neighboring tracks.

An apparatus can include a circuit configured to process an input signal using a set of channel parameters. The circuit can produce, using a first adaptation algorithm, a first set of channel parameters for use by the circuit as the set of channel parameters in processing the input signal. The circuit can further approximate a second set of channel parameters of a second adaptation algorithm for use by the circuit as the set of channel parameters in processing the input signal based on the first set of channel parameters and a relationship between a third set of channel parameters generated using the first adaptation algorithm and a fourth set of channel parameters generated using the second adaptation algorithm. In addition, the circuit can perform the processing of the input signal using the second set of channel parameters as the set of channel parameters.

Techniques provided herein compensate for an internal and external timing skew between a data strobe (DQS) and a clock (CLK), by: executing at least one write leveling initialization procedure (WLInit) that uses a mode-register-write (MRW) command to synchronize a timing between a data strobe (DQS) with a clock (CLK) based upon capture of an internal write command. Internal and external timing skew is identified based upon the WLInit. The internal timing skew is skew caused internal to a memory device and the external timing skew is skew caused external to the memory device. A timing between the DQS and the CLK is adjusted based upon the internal and external timing skew.

A disk device includes a first controller configured to determine a first operation amount of a first actuator based on a difference between a current position and a target position of a head, a second controller configured to determine a second operation amount of a second actuator based on the difference, and a processor. The processor is configured to perform a first filtering to calculate a first filter value based on a vibration detected at multiple points in time and filter coefficients, perform a second filtering to generate a second filter value based on the vibration detected at each of the multiple points in time, and update the filter coefficients based on the second filter values and a difference between the target position and an updated position of the head.

A PMR read/write head configured for thermally assisted recording (TAMR) includes thermally active bumper pads formed to each side of a write element to provide enhanced touchdown (TD) protection to the write head element where it emerges adjacent to the plasmon near-field spot produced by the TAMR apparatus. The bumper pads are disposed about the write head and absorb heat energy generated by active heating elements, the write current and the energy generated by the TAMR apparatus. Absorption of this energy causes the bumper pads to expand and protrude outward from the slider ABS to protect the read/write head from both intentional and unanticipated touchdown events. The PMR read/write head is then mounted on a slider and the assembly is incorporated into a hard disk drive (HDD).

A system for transition curvature improvement on thermally assisted magnetic recording, includes: an energy source, a thermally assisted magnetic recording head including a magnetic main pole for writing of a thermally assisted magnetic recording medium, a waveguide for directing an energy produced by the energy source, and a PPG including a peg and adjacent to the waveguide, the PPG being for turning the energy into a surface plasmon which travels down the peg to heat the thermally assisted magnetic recording medium. The magnetic main pole includes a first portion enabling a first magnetic field strength and at least one additional portion enabling a magnetic field strength stronger than the first magnetic field strength such that a magnetic field of the magnetic main pole along a horizontal direction thereof enables generation of a substantially straight transition curve while writing on the thermally assisted magnetic recording medium.