Abstract: Symmetrical or asymmetrical noise distributions for voltages corresponding to symbols that can be stored in multi-level memory cells (MLCs) of a memory device are used to determine read reference and/or programming voltages. The read reference voltages and/or programming voltages for the MLCs are jointly determined using the symmetrical distributions and a maximum likelihood estimation (MLE) and/or by determining at least one of the read reference voltages and the programming voltages using the asymmetrical distributions.

Abstract: A multi-stage sensor is situated on the head transducer and configured to interact with a magnetic recording medium. A first sensor stage of the multi-stage sensor has a temperature coefficient of resistance. A second sensor stage of the multi-stage sensor is coupled to the first sensor and has a temperature coefficient of resistance. The first sensor stage is configured to preferentially sense asperities of the media relative to the second sensor stage, and the second sensor stage configured to preferentially sense proximity to, and contact with, a surface of the media relative to the first sensor stage. The first and second sensor stages may be connected in series or in parallel.

Abstract: In a particular embodiment, a controller is adapted to control read/write access to a storage media including a pre-allocated area having multiple meta-blocks. The controller includes logic adapted to control the multiple meta-blocks as a first in first out (FIFO) circular queue. The logic selects one or more meta-blocks from the multiple meta-blocks based on an order associated with the FIFO circular queue and selectively writes a logical block address (LBA) mapping table to the selected one or more meta-blocks.

Abstract: Apparatus for recording data and method for making the same. In accordance with some embodiments, a magnetic recording layer is adapted to store data along perpendicular magnetic domains. A protective overcoat layer is formed on the magnetic recording layer to substantially protect the magnetic recording layer from environmental effects. The protective overcoat layer is made of carbon intermixed with at least one transition metal, such as but not limited to chromium.

Abstract: An implementation of a system disclosed herein provides a method of deferring decoding of a data sector received at a read channel of a storage device, in response to determining that a data sector cannot be decoded by a first decoder and storing the data sector for further processing by a second decoder.

Abstract: A magnetic element may be constructed in accordance with various embodiments as a data reader. The magnetic element can have at least a magnetic reader that contacts a top shield and is separated from a side shield on an air bearing surface (ABS). The side shield may be antiferromagnetically coupled to the top shield via a coupling layer disposed between the top and side shields.

Abstract: A skewed burnishing head arrangement is provided for burnishing the surface of a disc. The skewing of the burnishing head relative to the diameter perpendicular to a sweeping direction provides improved wiping action that catches loose particles and surface contamination, as well as performing aggressive asperity cutting and surface conditioning, while preventing particles from being embedded into a disc surface.

Abstract: An apparatus that includes a writer that includes a write pole, at least one return pole, a writer coil and a write pole tip, wherein the write coil wraps around the write pole such that the flow of electrical current through the write coil generates a magnetic flux at the write pole tip, and wherein the write coil has a writer coil shape; and a heater that includes a resistive material, wherein the heater has a heater shape that substantially matches the writer coil shape.

Abstract: Various aspects of the present disclosure are directed toward a disc drive apparatus having an inner enclosure structure that resides within an outer disc drive enclosure. The inner enclosure structure includes an environment-adsorption material, an inner volume of gas, and an aperture-defining membrane. The environment-adsorption material combines a first-type of molecules with a second-type of molecules that are present in the outer disc drive enclosure. Additionally, the aperture-defining membrane facilitates diffusion of the second-type of molecules into the inner enclosure structure and into contact with the environment-adsorption material to adsorb the second-type of molecules into the first-type of molecules, which reduces the volumetric pressure in the outer disc drive enclosure.

Abstract: A method of forming a patterned lapping plate by providing a working tool having a pattern comprising a plurality of raised teeth, each of the raised teeth having a base, at least one side wall, and a terminal end, and patterning the lapping plate with the tool to provide a working surface having an inverse pattern of the tool surface in the working surface of the lapping plate, the patterning process plastically deforming the working surface of the lapping plate.

Abstract: A slider that minimizes lubricant accumulation includes bearing surfaces that provide above ambient fluid pressure, a cavity located between two bearing surfaces and at least one step feature that is spaced apart from the bearing surfaces and is located in and protrudes from a floor of the cavity at a height that is less than a height of the bearing surfaces. The at least one step feature includes surfaces configured to diverge and converge airflow in the cavity.

Abstract: Various embodiments may be constructed with a trilayer stack that is positioned on an air bearing surface (ABS). The trilayer stack can be configured with a stripe height along an axis orthogonal to the ABS and with first and second magnetic free layers that each has an angled uniaxial anisotropy with respect to the ABS.

Abstract: Method and apparatus for mutably associating logical block addresses to physical blocks. A physical storage space is apportioned into one or more bands. A logical block address (LBA) from a logical space is assigned to one of the bands, and the LBA is mutably associated with a particular physical block (sector) at an associated physical block address (PBA) within the assigned band. Such mutable association preferably includes the writing of user data associated with the LBA to the associated physical sector. During a subsequent operation, user data associated with the LBA can be stored in a second physical sector in the assigned band. The physical storage space preferably comprises a magnetic recording medium, and some or all of the bands preferably utilize overlapping tracks. The logical space is preferably divided into sets of sequential LBAs, with non-adjacent sets assigned to the same band. Map data are used to track sector allocation status in each band.

Abstract: A light source is coupled to an input facet that directs light from the light source to a core layer of a waveguide and a gradient index material layer disposed beside the core layer along a portion of a propagation length of the waveguide. Light is launched from the light source into the input facet. In response, the gradient index material layer directs light to the core layer at least along the portion of the propagation length.

Abstract: An apparatus and associated method for a head gimbal assembly for data transduction in a data storage device with a heat assist laser. Various embodiments of the present invention are generally directed to a slider supporting at least a transducing element on an air bearing surface (ABS) and a laser assembly directly attached to a top side of the slider opposite the ABS. The laser assembly is positioned on the top side with no portion of the laser assembly extending past a longitudinal centerline of the slider.

Abstract: Provided herein is an apparatus, including a photon emitter configured for emitting photons onto a surface of an article; a first reflective surface and a second reflective surface configured to reflect the photons onto the surface of the article; and a processing means configured for processing signals from a photon detector array corresponding to photons scattered from surface features of the article.

Abstract: Various embodiments may be generally directed to a data storage device with at least a magnetic element having a magnetic stack positioned adjacent to and separated from at least one side shield on an air bearing surface (ABS). The side shield can be configured with a predetermined anisotropy variation along a down-track direction.

Abstract: Various embodiments can have a data read stack positioned on an air bearing surface (ABS). The data read stack may be disposed between first and second buffer layers, where at least one of the buffer layers can be configured to provide a predetermined shunt ratio for the data read stack.

Abstract: A light delivery system in a slider includes a channel waveguide, a solid immersion mirror, a near field transducer, and a planar waveguide assembly. The solid immersion mirror focuses light to the near field transducer. In one implementation, the slider includes a first reflective element and a second reflective element formed in the slider to induce an offset between a light source and the near field transducer. The reflective elements redirect light received from a light source between the reflective elements to a focusing element (e.g., a solid immersion mirror) focused on a near field transducer. The reflective elements translate the light in accordance with the offset between the light source and the near field transducer.

Abstract: A memory unit includes a magnetic tunnel junction data cell electrically coupled to a bit line and a word line. The magnetic tunnel junction data cell is configured to switch between a high resistance state and a low resistance state by passing a unipolar voltage across the magnetic tunnel junction data cell. A diode is electrically coupled between the magnetic tunnel junction data cell and the word line or bit line. A voltage source provides the unipolar voltage across the magnetic tunnel junction data cell that writes the high resistance state and the low resistance state.