Abstract: A method and a system for identifying a glacial lake outburst debris flow (GLODF) are provided. The method is obtained based on considering induced influences of slopes of channels and particle sizes of source particles on the GLODF. The method not only compensates for deficiencies in identifying the GLODF, but also realizes determination of the GLODF, which provides data basis for disaster prevention and control layout such as monitoring and early warning on a glacial lake and assists preventing and managing disasters caused by the GLODF. Meanwhile, multiple parameters used in the method are easy and convenient to obtain, and the parameters can be directly used on site, which saves engineering cost, improves working efficiency, and has high practical and promotional value in environmental protection and disaster prevention and mitigation.

Abstract: Embodiments of the present disclosure relate to magnetic recording heads (e.g., magnetic write heads) for magnetic recording devices (e.g., hard disk drives (HDD's)). A magnetic recording head includes, in a gap between a write pole and a trailing shield: a spin polarization layer (SPL), a free layer, and a spacer layer between the SPL and free layer. A spin torque layer (STL) is additionally included, and is separated from the free layer by a barrier layer that reduces or eliminates spin torque between the free layer and the STL. In one or more embodiments, to enable a thinner barrier layer, one or more dusting layers are inserted between the write pole and the trailing shield, and the one or more dusting layers are each formed of iron-chromium (FeCr). This helps maintain a thinner or narrower material stack in the gap and enhances writer performance.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head. The magnetic recording head comprises a main pole (MP), a shield, and a spintronic device disposed between the MP and the shield. The spintronic device comprises a MP notch disposed on the MP, a first spin torque layer (STL), a second STL, a spin kill layer disposed between the first and second STLs, and a shield notch. The spin kill layer prevents spin torque from being transferred between the first STL and the second STL. In a forward stack where electrons flow from the MP to the shield, the MP notch comprises FeCr and the shield notch comprises CoFe. In a reverse stack where electrons flow from the shield to the MP, the MP notch comprises CoFe and the shield notch comprises FeCr.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head. The magnetic recording head comprises a main pole, a shield, and a spintronic device disposed between the main pole and the shield. The spintronic device comprises two field generation layers (FGLs), two spin polarization layers (SPLs), and two spin kill layers. The spintronic device further comprises one or more optional thin negative beta material layers, such as layers comprising FeCr, disposed in contact with at least one of the spin kill layers. When electric current is applied, the spin kill layers and optional negative beta material layers eliminate or reduce any spin torque between the FGLs and the SPLs.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head having a first current flow in a cross-track direction through a trailing shield. In one or more embodiments, a second current flows in a cross-track direction around the main pole. The magnetic recording device comprises a main pole disposed between a trailing shield, a leading shield, and side shields. A trailing gap is disposed between the side shields and the trailing shield. A high moment seed layer is disposed between the main pole and the trailing shield. A first insulation layer is disposed within the trailing shield and directs the first current through the trailing shield, guided to the proximity of the main pole. A second insulation layer, disposed below the trailing shield, directs the second current through the trailing shield, or alternatively through the side shields and around the main pole.

Abstract: Embodiments of the present disclosure relate to magnetic recording heads (e.g., magnetic write heads) for magnetic recording devices (e.g., hard disk drives (HDD's)). A magnetic recording head includes, in a gap between a write pole and a trailing shield: a spin polarization layer (SPL), a free layer, and a spacer layer between the SPL and free layer. A spin torque layer (STL) is additionally included, and is separated from the free layer by a barrier layer that reduces or eliminates spin torque between the free layer and the STL. In one or more embodiments, to enable a thinner barrier layer, one or more dusting layers are inserted between the write pole and the trailing shield, and the one or more dusting layers are each formed of iron-chromium (FeCr). This helps maintain a thinner or narrower material stack in the gap and enhances writer performance.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head. The magnetic recording head comprises a main pole, a hot seed layer, and a spintronic device disposed between the main pole and the hot seed layer. The spintronic device comprises two field generation layers (FGLs), two spin polarization layers (SPLs), and two spin kill layers. The second SPL of the spintronic device drives the second FGL. The spintronic device further comprises one or more optional thin negative beta material layers, such as layers comprising FeCr, disposed in contact with at least one of the spin kill layers. When electric current is applied, the spin kill layers and optional negative beta material layers eliminate or reduce any spin torque between the FGLs and the SPLs.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head. The magnetic recording head comprises a main pole (MP), a shield, and a spintronic device disposed between the MP and the shield. The spintronic device comprises a MP notch disposed on the MP, a first spin torque layer (STL), a second STL, a spin kill layer disposed between the first and second STLs, and a shield notch. The spin kill layer prevents spin torque from being transferred between the first STL and the second STL. In a forward stack where electrons flow from the MP to the shield, the MP notch comprises FeCr and the shield notch comprises CoFe. In a reverse stack where electrons flow from the shield to the MP, the MP notch comprises CoFe and the shield notch comprises FeCr.

Abstract: A method for determining a consistency coefficient of a power-law cement grout includes: determining a water-cement ratio of the power-law cement grout; according to engineering practice requirements, determining a time required to determine the consistency coefficient of the power-law cement grout; and obtaining the consistency coefficient of the power-law cement grout. The method is accurate and reliable, requires less calculation, etc.; and has very high practical value and popularization value in environmental protection and ecological restoration.

Abstract: Aspects of the present disclosure generally relate to a magnetic recording head assembly that includes an external alternating current (AC) source. A magnetic recording head of the magnetic recording head assembly includes a conductive structure between a main pole and a trailing shield. The conductive structure includes a conductive layer, and the conductive layer is nonmagnetic. The magnetic recording head assembly also includes an external AC source to supply AC current that flows through the conductive structure. In one aspect, the conductive structure is between a coil structure and the trailing shield, and the external AC source is coupled to the coil structure. The conductive structure and the external AC source facilitate consistently providing an enhanced AC writing field to facilitate effective and reliable writing, high ADC, high SNR, and reduced jitter.

Abstract: A method for determining a three-dimensional tortuosity of a loose and broken rock-soil mass, includes the following steps: a particle grading curve of the loose and broken rock-soil mass is obtained by utilizing a particle size analysis, and followed by calculating an equivalent particle size and an average particle size; a porosity of the loose and broken rock-soil mass is obtained by utilizing a moisture content test, a density test, and a specific gravity test; the three-dimensional tortuosity of the loose and broken rock-soil mass is obtained by utilizing the equivalent particle size, the average particle size and the porosity of the loose and broken rock-soil mass. The method has the advantages of simple logic, accuracy and reliability, simple and fast parameter determination, and has high practical value and promotion value in the field of environmental protection and ecological restoration technology.

Abstract: Methods for identifying hydrocarbon contamination sources may include fingerprinting hydrocarbons using isotopocule analyses for BTEX compounds. For example, methods for identifying hydrocarbon contamination sources may comprise: extracting BTEX compounds from a sample; measuring the isotopocule composition of the BTEX compounds; and determining a characteristic of the sample based on the isotopocule composition. Such characteristics may include, but are not limited to, the characteristic of the sample comprises one or more selected from the group consisting of: a source of the sample, a condition at which the sample formed or was last equilibrated, a migration time from a source to a sample location, weathering of the sample, and degree to which the sample is anthropogenic and naturally-occurring.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head having a first current flow in a cross-track direction through a trailing shield. In one or more embodiments, a second current flows in a cross-track direction around the main pole. The magnetic recording device comprises a main pole disposed between a trailing shield, a leading shield, and side shields. A trailing gap is disposed between the side shields and the trailing shield. A high moment seed layer is disposed between the main pole and the trailing shield. A first insulation layer is disposed within the trailing shield and directs the first current through the trailing shield, guided to the proximity of the main pole. A second insulation layer, disposed below the trailing shield, directs the second current through the trailing shield, or alternatively through the side shields and around the main pole.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head having a first current flow in a cross-track direction through a trailing shield. In one or more embodiments, a second current flows in a cross-track direction around the main pole. The magnetic recording device comprises a main pole disposed between a trailing shield, a leading shield, and side shields. A trailing gap is disposed between the side shields and the trailing shield. A high moment seed layer is disposed between the main pole and the trailing shield. A first insulation layer is disposed within the trailing shield and directs the first current through the trailing shield, guided to the proximity of the main pole. A second insulation layer, disposed below the trailing shield, directs the second current through the trailing shield, or alternatively through the side shields and around the main pole.

Abstract: A heat-assisted magnetic recording (HAMR) head has a slider with a gas-bearing-surface (GBS). The slider supports a near-field transducer (NFT) and a main magnetic pole that has a step or recess in the NFT-facing surface near the GBS that contains plasmonic material. A thermal shunt is located between the NFT and the main pole to allow heat to be transferred away from the optical spot generated by the NFT. The NFT-facing surface of the main pole that is recessed from the step away from the GBS is in contact with the thermal shunt, and the thermal shunt is in contact with the plasmonic material in the step in the back region recessed from the GBS, so there is no increase in the spacing between the NFT and a large portion of the main pole.

Abstract: The present disclosure is generally related to a magnetic recording device comprising a magnetic recording head having a current flow in a cross-track direction around a main pole. The magnetic recording device comprises a main pole disposed between a trailing shield, a leading shield, and side shields. A trailing gap is disposed between the main pole and the trailing shield. A hot seed layer is disposed between the trailing gap and the trailing shield. A first insulation layer is disposed between the hot seed layer and the trailing shield, where the first insulation layer contacts the side shields. A second insulation layer is disposed between the main pole and leading shield, where the second insulation layer contacts the side shields. The first and second insulation layers direct the current through the side shields and across the main pole in a cross-track direction.

Abstract: Aspects of the present disclosure generally relate to a magnetic recording head assembly that includes an external alternating current (AC) source. A magnetic recording head of the magnetic recording head assembly includes a conductive structure between a main pole and a trailing shield. The conductive structure includes a conductive layer, and the conductive layer is nonmagnetic. The magnetic recording head assembly also includes an external AC source to supply AC current that flows through the conductive structure. In one aspect, the conductive structure is between a coil structure and the trailing shield, and the external AC source is coupled to the coil structure. The conductive structure and the external AC source facilitate consistently providing an enhanced AC writing field to facilitate effective and reliable writing, high ADC, high SNR, and reduced jitter.

Abstract: The invention relates to a method and an actuator system for determining and applying a voltage to a piezoelectric actuator (PEA) to achieve a given setpoint displacement. The method involves determining a relation dcal(V) between a PEA displacement measure (d) and voltage (V) and a relation ttcal(V) between transition time (tt) and voltage and combining the determined relations to calculate a relation d(tt) between the displacement measure and transition time during an initial calibration procedure. This relation is characteristic for the PEA, and by determining a new relation ttnew(V) after repeated biasing of the PEA, a compensated relation dc(V) can be calculated by substituting ttnew(V) in the calculated d(tt). The compensated relation dc(V) compensates for piezo creep effects due to the wear and can be used to determine the voltage to be applied directly, or be used in other compensation algorithms.

Abstract: The present disclosure generally relates to data storage devices, and more specifically, to a magnetic media drive employing a magnetic recording head. The head includes a main pole, a trailing shield, and a MAMR stack including at least one magnetic layer. The magnetic layer has a surface facing the main pole, and the surface has a first side at a media facing surface (MFS) and a second side opposite the first side. The length of the second side is substantially less than the length of the first side. By reducing the length of the second side, the area to be switched at a location recessed from the MFS is reduced as a current flowing from the main pole to the trailing shield or from the trailing shield to the main pole. With the reduced area of the magnetic layer, the overall switch time of the magnetic layer is decreased.

Abstract: The present disclosure relates to heat-assisted magnetic recording (HAMR) write heads including a waveguide and a main pole having a main pole tip. One or more current paths are provided through the main pole tip. Terminals of the one or more current paths can be coupled to the main pole, a trailing shield, a leading shield, a heat sink layer, a touch pad, a pole diffusion barrier layer, a NTS sensor, or another suitable component of the HAMR write head.