Abstract: The present disclosure relates to disk separator plates that include a coating to increase the water contact angle of the exterior surface of the disk separator plate so as to decrease its wettability. The present disclosure also involves hard disk drives that include such a disk separator plate and related methods of forming such a coating.

Abstract: A magnetic stack includes a substrate and a soft magnetic underlayer deposited on a top surface of the substrate. A heat sink layer is disposed on top of the soft magnetic underlayer, and an interlayer is deposited on top of the heat sink layer. A non-magnetic seed layer is deposited on top of the interlayer. A magnetic recording structure which includes more than one magnetic recording layer is deposited on the top surface of the non-magnetic seed layer.

Abstract: A system, apparatus, and method may include receiving edge device data, training a remote artificial intelligence (AI) model using the edge device data, and storing resulting remote AI model parameters in a ledger-based data structure. The ledger may also store device health data indicative of electronic device health of one or more edge devices. A ledger node may store a shared ledger. The shared ledger may use blockchain or encryption techniques and may store encrypted data, data pointers, or transfer data. The shared ledger may be accessible by at least two parties to share particular device health data.

Abstract: A method is disclosed for determining whether piezoelectric materials have defects such as cracks. The method includes applying a voltage signal to a piezoelectric micro-actuator, measuring a temperature of the piezoelectric micro-actuator while applying the voltage signal, and determining that the piezoelectric micro-actuator includes a defect based on the measured temperature.

Abstract: A hard disk drive includes a base deck that is coupled to a cover, a motor assembly that is coupled to the base deck, and magnetic recording media that is coupled to the motor assembly. The motor assembly includes a magnetic bearing with a horizontal magnetic bearing component and a vertical magnetic bearing component.

Abstract: A data storage medium includes a substrate, and a plurality of spaced-apart discrete data storage tracks supported by the substrate. The data storage medium also includes magnetic flux sinking material between the discrete data storage tracks and over the substrate. As an alternative to the magnetic flux sinking material, plasmonic material may be included between the discrete data storage tracks and over the substrate.

Abstract: A data storage system includes a logical space having logical block addresses (LBAs) divided into non-overlapping LBA ranges, and a physical space having pairs of physical bands. The system also includes a map in which first successive alternate LBAs of each different one of the non-overlapping LBA ranges are mapped to successive adjacent physical blocks of a first physical band of each different pair of the pairs of physical bands, and second successive alternate LBAs of each different one of the non-overlapping LBA ranges are mapped to successive adjacent physical blocks of a second physical band of each different pair of the pairs of physical bands. A controller employs the map to concurrently read data from a first physical block of the first physical band of one pair of physical bands and from a first physical block of the second physical band of the same pair of physical bands.

Abstract: A recording head has a near-field transducer that extends a first distance away from a media-facing surface. Two subwavelength focusing mirrors are at an end of a waveguide proximate the media-facing surface and extend a second distance away from the media-facing surface that is less than the first distance. The subwavelength mirrors are on opposite crosstrack sides of the near-field transducer and separated from each other by a crosstrack gap. The subwavelength focusing mirrors each include a first material at the media-facing surface and a plasmonic material that covers an edge of the subwavelength focusing mirror that faces the near-field transducer. The first material is more mechanically robust than the plasmonic material.

Abstract: A recording head has a near-field transducer proximate a media-facing surface of the recording head. A waveguide overlaps and delivers light to the near-field transducer. Two subwavelength focusing mirrors are at an end of the waveguide proximate the media-facing surface. The subwavelength mirrors are on opposite crosstrack sides of the near-field transducer and separated from each other by a crosstrack gap. The subwavelength focusing mirrors each include a core having a first edge exposed at the media-facing surface. The core formed of a core material that is resistant to mechanical wear and corrosion, such as a dielectric or robust metal. A liner covers a second edge of the core facing the near-field transducer. The liner includes a plasmonic metal that is different than the core material, such as Au or Al.

Abstract: A heat-assisted magnetic recording head includes a near-field transducer and a heat sink. The near-field transducer includes a middle disk and a near-field emitter. The near-field emitter includes a peg and an anchor disk. The peg is configured to produce a hot spot on a proximal magnetic disk. The peg is disposed proximal to a media-facing surface of the heat-assisted magnetic recording head. The anchor disk is disposed behind the peg relative to the media-facing surface. The heat sink includes a core and a liner. The core includes a primary metal, and the liner includes a primary metal. The liner is coupled to the core and is disposed along an outer surface of the core. The middle disk is disposed between and coupled to the liner and the anchor disk. The primary metal of the liner comprises at least one of iridium, rhodium, tantalum, tungsten, or ruthenium.

Abstract: A microfluidic device for polymerase chain reaction (PCR) processing includes a platform with a microstructure with at least one reaction chamber, and a heating element. The heating element heats at least a part of the at least one reaction chamber. The heating element includes at least one spin torque oscillator (STO) configured to heat the at least a part of the at least one reaction chamber to one or more temperatures for PCR processing.

Abstract: Systems and methods are disclosed for magnetoresistive asymmetry (MRA) compensation using a digital compensation scheme. In certain embodiments, a method may comprise receiving an analog signal at a continuous-time front end (CTFE) circuit, and performing analog offset compensation to constrain an extremum of the analog signal to adjust a dynamic range based on an input range of an analog-to-digital converter (ADC), rather than to modify the analog signal to have a zero mean. The method may further comprise converting the analog signal to a digital sample sequence via the ADC; performing, via a digital MRA compensation circuit, digital MRA compensation on the digital sample sequence; receiving, via a digital backend (DBE) subsystem, the digital sample sequence prior to digital MRA compensation; and generating, via a DBE, a bit sequence corresponding to the analog signal based on an output of the DBE subsystem and an output of the digital MRA compensation circuit.

Abstract: Methods are described for forming a mounting surface on a slider body. In one method, an adhesion layer can be deposited on a top surface of a slider body. A first photolithography cycle deposits a first metal layer having a first thickness of at least 8 ?m. A second photolithography cycle deposits a second metal layer having a second thickness of at least 8 ?m over the first metal layer. The first and second layer form a mounting support on the top surface. In another method, the top surface is etched to form a mounting support.

Abstract: A data storage device includes a base, a shaft that extends perpendicular from the base, and a head stack assembly (HSA) having a first end to which a head is coupled and a second end that is movably mounted on the shaft. The data storage device also includes either a first actuator assembly or a second actuator assembly. The first actuator assembly includes a first coil-permanent magnet assembly that rotatably moves the HSA about the shaft, and a second coil-permanent magnet assembly that serves as a first elevator to linearly move the HSA along the shaft. The second actuator assembly includes a third coil-permanent magnet assembly that rotatably moves the HSA about the shaft, and a second elevator that linearly moves the HSA along the shaft and also moves a data storage device ramp in unison with the HSA.

Abstract: A defect inspection system provides an image of a surface of a hard drive media to a machine learning model that is trained to identify predefined classifications of abnormal surface patterns on the hard drive media, each of the predefined classifications being associated in system memory with a severity indicator. The defect inspection model analyzes the image and generates and output indicating that the image includes a pattern consistent with a select classification of the predefined classifications of abnormal surface patterns. When the severity indicator for the select classification satisfies a failure condition, the defect inspection system automatically implements a corrective action.

Abstract: Two or more data values are received from one or more sensors of a hard disk drive. The two or more data values are indicative of a fly height of a recording head of the hard disk drive. The two or more data values are input into a machine-learning processor during operation of the hard disk drive. A fly height of the recording head during the operation of the hard drive head is adjusted based on an output of the machine learning processor.

Abstract: Components are extracted from user data being read from a reader of a hard disk drive. The components collectively indicate both a magnitude and direction of a read offset of the reader over a track. The components are input to a machine-learning processor during operation of the hard disk drive, causing the machine-learning processor to produce an output. A read offset of the reader is estimated during the operation of the hard drive head based on the output of the machine learning processor. While reading the user data, a radial position of the reader over the track is adjusted via an actuator based on the estimated read offset.

Abstract: A DNA sequencing device and methods of making. The device includes a pair of electrodes having a spacing of no greater than about 2 nm, the electrodes being exposed within a nanopore to measure a DNA strand passing through the nanopore. The device can be made by depositing a conductive layer over a sacrificial channel and then removing the sacrificial channel to form the electrode gap.

Abstract: A data storage device can employ a front end bus for boot operations. The physical connection of a secure boot assembly to the front end bus can provide efficient and reliable booting of the data storage device without a connection to a remote host or network. A secure boot assembly can provide a security module that connects to the boot module of the data storage device to authenticate a trustworthiness of the data storage device while the data storage device is disconnected from any remote host.

Abstract: A method for distributed and private symmetric searchable encryption includes receiving encrypted data, creating a search index for one or more servers based on the encrypted data using a distributed point function (DPF), splitting the encrypted data into a number of portions based on the number of servers, and partitioning the servers into two or more groups. The method also includes updating the search index based on the splitting and the partitioning, transmitting the split encrypted data to the servers based on the updated search index, verifying the transmitted data using data not transmitted to the server, and determining, based on the verifying, whether any server deviated from an assigned protocol.