Abstract: Devices having an air bearing surface (ABS), the device including a near field transducer, the near field transducer having a peg and a disc, the peg having a region adjacent the ABS, the peg including a plasmonic material selected from gold (Au), silver (Ag), copper (Cu), ruthenium (Ru), rhodium (Rh), aluminum (Al), or combinations thereof; and at least one other secondary atom selected from germanium (Ge), tellurium (Te), aluminum (Al), antimony (Sb), tin (Sn), mercury (Hg), indium (In), zinc (Zn), iron (Fe), copper (Cu), manganese (Mn), silver (Ag), chromium (Cr), cobalt (Co), and combinations thereof, wherein a concentration of the secondary atom is higher at the region of the peg adjacent the ABS than a concentration of the secondary atom throughout the bulk of the peg. Methods of forming NFTs are also disclosed.

Abstract: A data storage system can have adaptive data path routing that consists of a network controller connected to a plurality of data storage units that each have a local controller and memory. A front-end module of the network controller may direct a first data set from a first data storage unit of the plurality of data storage units via a primary data. A back-end routing module of the network controller can adapt to an amount of data accesses by transferring a second data set from a second data storage unit of the plurality of data storage units via a back-end data path.

Abstract: Method and apparatus for managing data in a semiconductor memory, such as but not limited to a three dimensional (3D) NAND flash memory array. In some embodiments, the memory has non-volatile memory cells arranged into addressable blocks. Each memory cell is configured to store multiple bits. A program/read control circuit programs data sets to and reads data sets from the memory cells in the addressable blocks to service a sequence of host access commands. The circuit concurrently performs background reads in conjunction with the servicing of the host access commands. The background reads result in the reading of a different data set from each of the addressable blocks over each of a succession of time intervals of selected duration. The background reads condition the memory cells prior to a first read operation associated with the host access commands.

Abstract: Bottom tracks are written to a recording medium using a first setting of a spin-torque oscillator of a single microwave assisted magnetic recording (MAMR) head. Top tracks are written interlaced between and partially overlapping the bottom tracks using the single MAMR head at a second setting of the MAMR head, the first and second settings resulting in different bit aspect ratios for the top and bottom tracks.

Abstract: An apparatus may include a baseboard management controller (BMC) configured to monitor one or more statuses of a storage array enclosure of the BMC. The BMC may further communicate with a host device of a PCIe network topology via a PCIe port of the BMC including performing a direct memory access (DMA) write to store status information of the enclosure to a memory of the host device via the PCIe network topology and performing a DMA read to retrieve control information from the memory of the host device via the PCIe network topology. In addition, the BMC may control one or more devices of the storage array enclosure based on the retrieved control information.

Abstract: Aspects of the disclosure are directed to apparatuses and methods involving an apparatus operable for read/write access to data storage media. As may be consistent with one or more embodiments, a hard disc drive apparatus includes respective e-blocks mounted in different corners of an enclosure (e.g., base deck) having storage media therein. Each e-block has one or more actuator arms having a read/write head thereon and a voice coil that rotates the actuator arm about an axis. The respective e-blocks are operable for read/write access to different regions of the storage media (e.g., with a longer actuator arm utilized for accessing an inner region of disc media, and a shorter actuator arm utilized for accessing an outer region of disc media). The number, size and rotational limits of the respective e-blocks are utilized to facilitate the use of a compact enclosure design while achieving high-speed data access.

Abstract: Systems and methods are disclosed for timing servo operations within a channel based on a counter for a disc locked clock. In certain embodiments, an apparatus may comprise a servo channel configured to lock a frequency of a servo channel clock to a rotational velocity of a disc data storage medium, and maintain a counter of clock cycles for the servo channel clock. The servo channel may perform operations to read servo data from a servo sector on the disc data storage medium at a first counter value selected relative to a target counter value corresponding to an expected location of a servo timing mark (STM).

Abstract: A method of lapping multiple row bars provided in a stack, including the steps of electrically connecting at least one row bar bond pad of a first row bar to at least one carrier bond pad of a carrier, electrically connecting an outermost row bar of the stack to the first row bar of the stack by at least one electrical trace, wherein the outermost row bar comprises at least one electronic lapping guide, lapping an outer surface of the outermost row bar until a signal provided by the at least one electronic lapping guide of the outermost row bar reaches a predetermined value, terminating the lapping of the outermost row bar, and removing the outermost row bar from the stack to expose a second row bar, wherein the second row bar is electrically connected to the first row bar with the at least one electrical trace.

Abstract: Methods, systems and computer-readable storage media for receiving, via an external interface of a storage device, a command from a computing host, the command including at least one non-standard command modifier, executing the command according to a particular non-standard command modifier, storing an indication of the particular non-standard command modifier in an entry of a map associated with a logical block address of the command, and storing a shadow copy of the map in a memory of the computing host.

Abstract: An apparatus includes a first waveguide core extending along a light-propagation direction and configured to receive light from a light source at a combined transverse electric (TE) mode and a transverse magnetic (TM) mode. A second waveguide core is spaced apart from the first waveguide core and is configured to couple light at a TM mode to the second waveguide core. A near-field transducer (NFT) is disposed at a media-facing surface of a write head, the NFT receiving the light from the first waveguide core or the second waveguide core and heating a magnetic recording medium in response thereto.

Abstract: A method includes generating, during manufacture of a heat-assisted magnetic recording (HAMR) disk drive, a temperature compensation equation for a compensation factor using initial operating currents supplied to a laser diode of the disk drive at different initial operating temperatures and an efficiency value based on the initial operating temperatures. The operating currents are representative of currents for recording data to or erasing data from a magnetic recording medium. The temperature compensation equation is stored in the disk drive. A subsequent efficiency value is determined based on at least one of the initial operating temperatures and an operating temperature differing from the initial operating temperatures. An updated compensation factor at the operating temperature is determined during field operation using the temperature compensation equation and the subsequent efficiency value. An updated operating current is calculated using the updated compensation factor and the operating temperature.

Abstract: First tracks are read via a first head that is moved via a first actuator over a first, radially-defined, zone of a disk surface. Second tracks are read via a second head that is moved via a second actuator over a second zone of the disk surface that is separate from the first zone. The first and second heads are optimized to read data within first and second skew angle ranges associated with the first and second zones. The first and second skew angle ranges are each less than a total skew angle range of the disk surface.

Abstract: Devices that include a near field transducer (NFT) including a crystalline plasmonic material having crystal grains and grain boundaries; and nanoparticles disposed in the crystal grains, on the grain boundaries, or some combination thereof, wherein the nanoparticles are oxides of, lanthanum (La), barium (Ba), strontium (Sr), erbium (Er), hafnium (Hf), germanium (Ge), or combinations thereof; nitrides of zirconium (Zr), niobium (Nb), or combinations thereof; or carbides of silicon (Si), aluminum (Al), boron (B), zirconium (Zr), tungsten (W), titanium (Ti), niobium (Nb), or combinations thereof.

Abstract: A recording head includes a near-field transducer proximate a media-facing surface. The near-field transducer comprises an aperture portion surrounded by walls of plasmonic material, the walls oriented normal to the media-facing surface. A notch protrudes within the aperture. The notch comprises at least one of Rh and Ir. A write pole is proximate the near-field transducer. The write pole has a back surface facing away from the media-facing surface and an aperture-facing surface proximate the aperture.

Abstract: Apparatus and method for enacting data security in a cryptographic processing system, such as a data storage device. In some embodiments, a timer circuit is initiated to denote an elapsed time interval of predetermined duration responsive to a function call by an initiator circuit to perform a selected cryptographic function upon input data. The selected cryptographic function is executed to generate output data which are temporarily stored in a memory location during a waiting period prior to a conclusion of the elapsed time interval. Additional functions may be performed during the waiting period. A notification from the timer circuit is received at the conclusion of the elapsed time interval, and the output data are transferred from the memory to the initiator circuit. In this way, a timing attack may be defended against by configuring the selected cryptographic function to have the same overall execution time for different input data sets.

Abstract: Provided herein is an apparatus including a hard drive base. A number of disks are rotatably connected to the hard drive base, and there are a number of disk gaps between the disks. A shroud extends in a circumferential span around the disks, wherein the shroud extends less than the circumference of the disks. The shroud is positioned between the disk gaps and an upwardly sloping gas channel. A number of arcuate gas channels are in the shroud, wherein each arcuate gas channel is horizontally aligned with a corresponding disk gap. The arcuate gas channels connect the disk gaps to the upwardly sloping gas channel.

Abstract: A data storage device includes a data store optimized organized into allocation units sized according to an sequential writing unit or garbage collection unit of the data store. Information is written to the allocation units as either coarse or fine-grained packets, which are packets of data that are self-describing and written together. Random writes received from a host to data already written into allocation units is written to another allocation unit, and a coarse-grained forward map is updated to reflect the physical location of the valid data that superseded data in the allocation unit until the allocation unit can be rewritten. Promotion operations are disclosed to compact data and garbage collect data by rewriting allocation units.

Abstract: Data targeted for storage into a drive array is divided into codewords with data and parity symbols. The symbols of the codewords are randomly distributed across a stripe of the drive array. One or more drives affected by data corruption are found based on a probability that a subset of inconsistent codewords intersects the one or more drives.

Abstract: A faulty tracking condition affecting a first head driven by a first actuator of a hard disk drive is determined. The faulty tracking condition is caused by a second actuator of the hard disk drive that is moving while the first actuator is performing a tracking operation. Responsive to the determination of the faulty tracking condition, seek forces of the second actuator that cause the faulty tracking condition affecting the first head are reduced. A controller verifies that similar faulty tracking conditions are reduced with the first head in response to the reduction in seek forces.

Abstract: Methods are presented suitable for clustering computational event logs (2) including a method for calculating a metric distance between characters of different event messages (4) by comparing both characters to a comparative set of characters. Methods are presented for calculating a metric distance between two event messages (4) comprising determining character metric distances between characters in the compared words and word metric distances between the words in the compared events (4), Methods are presented for creating an area (8) in metric space corresponding to a new cluster (6) when a further event message (26) is found in an overlap region (24) of existing clusters (6, 8). Methods are presented in populating and constructing an event table.