A magnetic head includes a medium facing surface, a coil, a main pole, and a substrate. The main pole includes a first layer, and a second layer lying on the first layer. The first layer includes a thickness-changing portion whose dimension in a direction perpendicular to a top surface of the substrate decreases with decreasing distance to the medium facing surface. At least part of the second layer is located on the thickness-changing portion.

A magnetic head, according to one embodiment, includes a rowbar substrate having a tape support surface and a gap surface at a substrate edge. A closure is positioned opposite the gap surface of the rowbar substrate, the closure forming a portion of the tape support surface. A recessed gap region is interposed between the gap surface of the rowbar substrate and the closure, the recessed gap region having a recessed gap profile that extends between the gap surface of the rowbar substrate and the closure, the recessed gap region having a transducer row with at least one magnetic sensor on the gap surface of the rowbar substrate. An insulation layer is positioned over the recessed gap profile of the recessed gap region.

An apparatus according to one approach includes a servo reader transducer structure on a module. The servo reader transducer structure has a lower shield, an upper shield above the lower shield, the upper and lower shields providing magnetic shielding, a current-perpendicular-to-plane sensor between the upper and lower shields, an electrical lead layer between the sensor and one of the shields, and a spacer layer between the electrical lead layer and the one of the shields. The electrical lead layer is in electrical communication with the sensor. The conductivity of the electrical lead layer is higher than the conductivity of the spacer layer. An array of writers is also present on the module. Writer modules having this structure are less susceptible to shorting, and therefore enable use of TMR servo readers on writer modules.

A server box embodiment is disclosed that generally comprises an array of dummy HDDs that share a common set of universal disk drive components in a master components module, or power module. Each dummy HDDs is constructed without expensive onboard chipsets that control the normal functionality of a standard HDD. By sharing expensive chipsets in a master components module (power module) money can be saved in building and selling the dummy HDD server. Embodiments envision a power module possessing the needed chipset functionality that is missing in a dummy HDD. The power module can be made to move from dummy HDD to dummy HDD supplying the necessary chipset in a shared manner when data is being stored or retrieved for client or end-user.

Disclosed herein are magnetic write heads and methods of designing them, and data storage devices comprising such write heads. A magnetic write head having leading and trailing sides comprises an air-bearing surface (ABS), a main pole between the leading and trailing sides, a first return pole between the main pole and the leading side, at least one optical near-field generator between the first return pole and the main pole, and a second return pole between the main pole and the trailing side. The main pole comprises a first tapered portion comprising a leading-side edge perpendicular to the ABS, a first trailing-side edge at a first angle to the ABS, and a second trailing-side edge recessed from the ABS and at a second angle to the ABS. The second return pole comprises a second tapered portion adjacent to the ABS and extending toward the main pole.

Disclosed herein are magnetic write heads and methods of designing them, and data storage devices comprising such write heads. A magnetic write head having leading and trailing sides comprises an air-bearing surface (ABS), a main pole between the leading and trailing sides, a first return pole between the main pole and the leading side, at least one optical near-field generator between the first return pole and the main pole, and a second return pole between the main pole and the trailing side. The main pole comprises a first tapered portion comprising a leading-side edge perpendicular to the ABS, a first trailing-side edge at a first angle to the ABS, and a second trailing-side edge recessed from the ABS and at a second angle to the ABS. The second return pole comprises a second tapered portion adjacent to the ABS and extending toward the main pole.

Dual and triple PMR writers are disclosed wherein the number of writer pads required to energize the selected PMR writer is minimized to three or four, respectively, with a coil configuration wherein separate top coils are connected by separate interconnects or side taps to separate bottom coils. Either top coils or bottom coils may be linked to a common W pad. Alternatively, there may be one bottom coil that allows all output current to flow to a common W pad. Coils may have a pancake or helical shape. In dual PMR writer embodiments, there may be one or two dynamic fly height heater coils. Magnetic performance in the selected writer of a dual PMR writer is similar to that of a single PMR writer with regard to erase width in AC mode (EWAC), Hy field, trailing and side shield return fields, down-track and cross-track gradient.

An apparatus according to one approach includes a servo reader transducer structure on a module. The servo reader transducer structure has a lower shield, an upper shield above the lower shield, the upper and lower shields providing magnetic shielding, a current-perpendicular-to-plane sensor between the upper and lower shields, an electrical lead layer between the sensor and one of the shields, and a spacer layer between the electrical lead layer and the one of the shields. The electrical lead layer is in electrical communication with the sensor. The conductivity of the electrical lead layer is higher than the conductivity of the spacer layer. An array of writers is also present on the module. Writer modules having this structure are less susceptible to shorting, and therefore enable use of TMR servo readers on writer modules.

An apparatus according to one embodiment includes a module having a plurality of tunnel valve read transducers arranged in an array extending along the tape bearing surface of the module. Each of the tunnel valve read transducers has upper and lower shields for providing magnetic shielding. A sensor structure is positioned between the shields. An electrical lead layer is positioned between the sensor structure and one of the shields. The electrical lead layer is in electrical communication with the sensor structure. A spacer layer is positioned between the electrical lead layer and the one of the shields. A conductivity of the electrical lead layer is higher than a conductivity of the spacer layer. At least some of the sensor structures are recessed from a plane extending along the tape bearing surface. An at least partially polycrystalline coating is positioned on a media facing side of the recessed sensor structures.

An apparatus according to one embodiment includes a module having a plurality of tunnel valve read transducers arranged in an array extending along the tape bearing surface of the module. Each of the tunnel valve read transducers has upper and lower shields for providing magnetic shielding. A sensor structure is positioned between the shields. An electrical lead layer is positioned between the sensor structure and one of the shields. The electrical lead layer is in electrical communication with the sensor structure. A spacer layer is positioned between the electrical lead layer and the one of the shields. A conductivity of the electrical lead layer is higher than a conductivity of the spacer layer. At least some of the sensor structures are recessed from a plane extending along the tape bearing surface. An at least partially polycrystalline coating is positioned on a media facing side of the recessed sensor structures.