Patent classifications
G11B5/607
Slider air bearing designs with higher pressure and higher thermal flying height (TFC) efficiency
Disclosed herein are sliders with at least one notch-cut in the trailing pad, methods of making them, and data storage devices comprising them. In some embodiments, a slider comprises a leading-edge surface, a trailing-edge surface, and an air-bearing surface (ABS) that includes a trailing pad situated closer to the trailing-edge surface than to the leading-edge surface, wherein the trailing pad comprises at least one notch-cut (e.g., two notch-cuts) in a trailing side of the trailing pad. The at least one notch-cut provides higher pressure at the recording head situated in the trailing pad and higher thermal flight control efficiency without a commensurate increase in touch-down power. As a result, the temperature around the recording head is lower than without the at least one notch-cut, thereby improving the lifetime of the recording head and data storage device.
Thermally-assisted magnetic recording (TAMR) head with magnetic assist current
The present embodiments relate to a thermally-assisted magnetic recording (TAMR) head. A magnetic assist current can be applied to the TAMR head to assist in reducing timing jitter as the TAMR head interacts with a magnetic recording material. The TAMR head can include a main write pole including a tip portion and configured to direct a magnetic field for interacting with a magnetic recording medium. The TAMR head can include a laser diode to heat the magnetic recording medium and a dynamic fly height (DFH) heating element for dynamically controlling a height of the main write pole. The heating element can be of a parallel bias circuit that directs a direct current (DC) bias current flow along an electrical path from the magnetic yoke element to the tip portion of the main write pole adjacent to an air bearing surface (ABS).
Data storage device with adaptive write policy and enhanced longevity
Illustrative aspects are directed to a data storage device comprising one or more disks; an actuator mechanism comprising one or more heads, and configured to position a head proximate to a disk surface; and one or more processing devices. The one or more processing devices are configured to: measure a read quality of a location on the disk surface; modify a refresh frequency for performing refresh writes at the location, based on the read quality at the location; in response to the refresh frequency at the location becoming stabilized, determine an integrated track interference (xTI) per write metric at the location; and, in response to determining that the xTI per write metric at the location is below a threshold for the xTI per write metric, modify an operating parameter of the head at the location to improve a longevity metric.
MAGNETIC DISK DEVICE
According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a control unit, and a setting unit. The magnetic head includes a write element which writes data to the magnetic disk and heater elements which adjust a levitation amount relative to the magnetic disk. The setting unit sets a heater value to be set on the basis of a measurement result of measuring the recording quality of the data written to the magnetic disk. The control unit controls electric power to be supplied to the heater elements on the basis of the heater value to be set to the setting unit.
READER FLY HEIGHT CONTROL FOR HEAD BURNISHING MITIGATION
A storage device includes a controller that determines a degree of data degradation for a data track targeted by a pending read command and sets a head/media clearance parameter for execution of the read command based on the determined degree of data degradation for the data track, the head/media clearance parameter providing for a greater head-media separation when the determined level of degradation is lower than when the determined level of degradation is higher.
Method to measure thermal protrusion by sensing spacing change due to pre-lasing
Various illustrative aspects are directed to a data storage device, comprising: one or more disks; an actuator assembly comprising a head, and configured to position the head over a corresponding disk surface; and one or more processing devices, the head comprising: a write element; a laser unit; and a fly height control element, and wherein the one or more processing devices are configured to: iteratively perform spiral write operations of spiral patterns comprising a plurality of sync marks with the head on the corresponding disk surface, wherein the spiral write operations are performed at: a plurality of values of laser pre-bias current, write backoff, and/or start disk phase; detect pattern signal amplitudes of the spiral patterns on the corresponding disk surface; and determine a relation of write backoff to laser pre-bias current for the head, based on the pattern signal amplitudes of the spiral patterns.
MAGNETIC DISK DEVICE
According to one embodiment, a magnetic disk device includes a rotatable disk-shaped recording medium, a magnetic head including a write head having a main magnetic pole that applies a recording magnetic field to the recording medium, an assist element that assists magnetic recording by the main magnetic pole, and a plurality of thermal actuators that control a head gradient with respect to the recording medium, and a controller which includes a detection unit configured to detect deterioration of the magnetic head, and changes a head gradient of the magnetic head by the thermal actuator according to the detected deterioration.
ESTIMATING RECORDING HEAD FLY HEIGHT USING MACHINE LEARNING
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
Energy-assisted magnetic recording head with protective cap
Aspects of the present disclosure provide various magnetic recording slider structures and fabrication methods that can reduce head overcoat (HOC) thickness without significantly reducing the lifetime and reliability of a slider by using a protective cap placed on preselected locations on the outermost surface or HOC of the slider. A slider includes a writer comprising an energy-assisted recording element. The writer is configured to store information on a magnetic medium using the energy-assisted recording element. The slider includes a head overcoat (HOC) layer providing an outermost media facing surface. The slider further includes a protective cap positioned on the HOC layer to at least partially cover the energy-assisted recording element, the protective cap including a preselected shape configured to protect the energy-assisted recording element.
Magnetic disk device
According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, a control unit, and a setting unit. The magnetic head includes a write element which writes data to the magnetic disk and heater elements which adjust a levitation amount relative to the magnetic disk. The setting unit sets a heater value to be set on the basis of a measurement result of measuring the recording quality of the data written to the magnetic disk. The control unit controls electric power to be supplied to the heater elements on the basis of the heater value to be set to the setting unit.