Abstract: In a heat-assisted magnetic recording head for use in a hard disk drive, a thermal shunt is positioned between an E-antenna near field transducer (NFT) and a return pole, to draw excess heat away from the NFT region. The thermal shunt comprises two portions separated by a gap that has a trapezoidal cross-section, where the NFT-side of the gap is wider than the return pole-side of the gap.

Abstract: A method of radially positioning a heat assisted magnetic recording (HAMR) head writes data to a first band, wherein a radial position of the HAMR head within each data track is defined by a positional bias and a track location. A determination is made regarding whether a threshold has been reached with respect to the first band. If the write threshold has been reached with respect to the first band, then the positional bias associated with the first band is modified to evenly distribute thermal exposure of data tracks in the first band.

Abstract: A system and method for decreasing power consumption of hard disk drives through use of an external atmosphere of low density gas, such as helium, is described. An environment container reasonably resistant to diffusion and leakage of helium (container) is erected around an existing hard disk array or server, wherein a helium mixture is pumped into the container. The helium mixture within the container is maintained at a specified concentration via proper tubing and valves which may be manually or automatically controlled. The actual concentration need not be very pure in order to achieve reduced drag over the disks in each of the hard disk drives, thereby achieving reduced power consumption. The environment container is stand alone from the hard disk drives used such that an altered hard disk apparatus is unnecessary.

Abstract: A data storage device and method for enabling dynamic fly height control which is insensitive to off-track motions is described. In some embodiments, a hard disk drive acquires signal data from neighboring overlapping tracks which are unwritten, thermally erased, or AC demagnetized. Side-to-side (off-track) positional errors or oscillations of the read head do not affect the signal which arises solely from the magnetic domains on the disk. Thus, signal variations may only arise from changes in the fly height. In other embodiments, neighboring overlapping data tracks are prewritten with reference data. The width of the neighboring overlapping tracks exceeds any expected side-to-side positional errors of the read head, thus signal variations may only arise from changes in the fly height. For all embodiments, the noise or reference data signal may serve as a reliable dynamic measure of the fly height with no effects arising from off-track motions.

Abstract: A method, apparatus, and system for implementing contact sensing are provided using a near field transducer (NFT) and in-drive NFT characterization diagnostics for heat-assisted magnetic recording (HAMR) hard disk drives (HDDs). NFT resistance is monitored and used to determine head to disk contact and spacing. NFT resistance is used to detect NFT head wear.

Abstract: A heat-assisted magnetic recording (HAMR) head has a protective film confined to a window of the disk-facing surface of the slider than surrounds the near-field transducer (NFT) and write pole end. Materials for the protective film include TiO2, ZrO2, HfO2, Nb2O5, Ta2O5, Sc2O3, Y2O3, MgO SiN, BN, SiBN and SiBNC. The slider overcoat is located in the non-window region on the slider's disk-facing surface and optionally also on the window region, with the outer surface of the overcoat forming the slider's ABS. An optional recess may be formed on the disk-facing surface of the slider in the window region, with the protective film located in the recess.

Abstract: Techniques for improving the recording quality during heat assisted magnetic recording (HAMR) by monitoring the power of a source used to heat a storage medium are described. In one example, a source emits electromagnetic radiation. A waveguide transmits the electromagnetic radiation onto a surface of a magnetic media. A photoresistive material is proximately located to the waveguide. The resistance of the photoresistive material varies based on the intensity of electromagnetic radiation propagating through the waveguide. The power of the source is determined by measuring the resistance of the photoresitive material. The power of the source is adjusted based on the determined power.

Abstract: A heat-assisted magnetic recording (HAMR) disk drive with a primary waveguide that directs laser light from a laser diode to a near-field transducer includes a second waveguide for sensing the head-disk spacing or fly-height. The second waveguide has a sensor portion that senses the spacing and directs light representative of the spacing to the second waveguide's output end. The second waveguide may include a second or reference portion that is connected to the sensor portion and directs light representative of light input from the laser diode. The combined light from the two portions is directed to the second waveguide's output end. A detector, which may be a photo-diode, is located at the second waveguide's output end and provides a signal that may be coupled to a thermal fly-height controller to increase or decrease the fly-height.

Abstract: A recessed near field transducer (NFT) in a heat-assisted magnetic recording head is manufactured by applying Joule heating to the slider to induce a protrusion of materials of and around the NFT and, while applying the Joule heating, removing the protrusion by lapping the slider. Removing the induced protrusion in this manner causes the NFT to recess into the body of the slider at ambient temperature, whereby during HAMR operation when optical power is being applied to a disk via the NFT, the NFT is substantially flush with the slider air bearing surface.

Abstract: In one general embodiment, a magnetic head includes a slider having a media-facing surface; and a device coupled to the slider and being selectively extendible for selectively contacting a magnetic medium at a frequency of between about 200 and about 600 kHz. Other magnetic heads and methods of use are described according to additional embodiments.

Abstract: Systems and methods from loading/unloading a data head for a disk drive provide for more efficient use of disk space. A method of loading/unloading a data head for a disk drive comprises determining a disk phase of a spinning disk arrangement, determining a loading/unloading position based on the disk phase, and loading or unloading the data head on or from, respectively, the spinning disk arrangement based on the determined disk phase. The determining a disk phase may be based on zero crossing of voltages for a three-phase motor associated with the spinning disk arrangement.

Abstract: A thermally-assisted recording (TAR) disk drive operates by turning on write current prior to the application of heat to the recording layer by the near-field transducer (NFT). In a TAR disk drive that uses thermal fly-height control (TFC), TFC power is at a first power level that keeps the write pole at a predetermined fly-height. The write current is then turned on, either simultaneously with or after a reduction in TFC power. The write pole then reaches its optimal fly-height as a result of the combination of write pole protrusion caused by the write current and retraction of the write pole caused by the reduction in TFC power. After the write pole has reached its optimal fly-height, heat is applied to the recording layer by the NFT. The combination of write current and heat causes writing to occur at the optimal write pole fly-height.

Abstract: A data storage device and method for enabling dynamic fly height control which is insensitive to off-track motions is described. In some embodiments, a hard disk drive acquires signal data from neighboring overlapping tracks which are unwritten, thermally erased, or AC demagnetized. Side-to-side (off-track) positional errors or oscillations of the read head do not affect the signal which arises solely from the magnetic domains on the disk. Thus, signal variations may only arise from changes in the fly height. In other embodiments, neighboring overlapping data tracks are prewritten with reference data. The width of the neighboring overlapping tracks exceeds any expected side-to-side positional errors of the read head, thus signal variations may only arise from changes in the fly height. For all embodiments, the noise or reference data signal may serve as a reliable dynamic measure of the fly height with no effects arising from off-track motions.

Abstract: TAR enable write heads may use a plasmonic device (e.g., an optical transducer) which uses electromagnetic energy generated from a laser to heat the magnetic media. However, as the temperature of the plasmonic device rises, the likelihood of stressing the material of the device or other materials of the head near the plasmonic device increases. Accordingly, the write head may include a temperature sensor proximate to the plasmonic device. In one embodiment, the resistance of the temperature sensor may change according to the temperature of the plasmonic device. Based on the measured resistance of the temperature sensor, a sensing circuit may adjust the power of the laser, and thus, prevent the stressing of the materials. Moreover, the thermal coupling between the temperature sensor and a heat sink connected to the plasmonic device may be improved by moving elements associated with the sensing circuit closer to a heat sink.

Abstract: A novel method and apparatus is provided for printing magnetic patterns using heat assisted magnetic recording (HAMR). The apparatus includes an array of probes that is arranged in a predetermined pattern, such as a servo pattern. The array of probes is brought into contact, or near-contact, with a magnetic recording medium that has been bulk erased substantially along an initialization direction. Each probe is energized so as to heat its respective contacted (or near-contacted) region of the recording medium above a threshold temperature. An external magnetic field is applied to the heated regions in a direction that is substantially opposite from the initialization direction. The strength of the external magnetic field is chosen to be greater than the coercivity of the recording medium at the threshold temperature, but less than the coercivity of the recording medium at room temperature. As a result, only magnetizations in the heated regions become aligned with the external field.

Abstract: An optical laser-activated TAMR (Thermal Assisted Magnetic Recording) slider, when normally mounted on a flexure, has an optical laser as well as other elements of its optical system exposed and subject to damage by mechanical shocks. The stand-off protective device disclosed herein, formed separately and attached to the flexure, or formed as part of the flexure itself, can protect the optical elements of such a slider from these shocks, particularly from inadvertent contacts with adjacent sliders or mechanical limiters.

Abstract: A slider mounted TAMR (Thermal Assisted Magnetic Recording), DFH (Dynamic Flying Height) type read/write head using optical-laser generated surface plasmons in a small antenna to locally heat a magnetic medium, uses the same optical laser at low power to pre-heat the antenna. Maintaining the antenna at this pre-heated temperature, approximately 50% of its highest temperature during write operations, allows the DFH mechanism sufficient time to compensate for the thermal protrusion of the antenna at that lower temperature, so that thermal protrusion transients are significantly reduced when a writing operation occurs and full laser power is applied. The time constant for antenna protrusion is less than the time constant for DFH fly height compensation, so, without pre-heating, the thermal protrusion of the antenna due to absorption of optical radiation cannot be compensated by the DFH effect.

Abstract: In one general embodiment, a magnetic head includes a slider having a media-facing surface; and a device coupled to the slider and being selectively extendible for selectively contacting a magnetic medium at a frequency of between about 200 and about 600 kHz. Other magnetic heads and methods of use are described according to additional embodiments.

Abstract: Instead of using discontinuous step functions or pulses to drive a laser of a TAR enabled disk drive between on and off, a fixed modulation frequency may be used that alternates between a high and low laser power such that the radiation source is always delivering heat to the magnetic media when writing data to the magnetic disk. The magnetic field of the write pole may be synchronized to the modulation frequency of the radiation source to ensure that the radiation source heats the magnetic media proximate to the write pole above the grain freezing temperature when the Zeeman energy produced by the magnetic field of the write pole exceeds the thermal energy of the magnetic media.

Abstract: An apparatus according to one embodiment includes a near-field transducer positioned towards an air bearing surface side of the apparatus; and at least one conductor or circuit for causing heating of the near-field transducer. A method according to one embodiment includes heating the near-field transducer by passing a current through the at least one conductor or circuit; and illuminating the near-field transducer during a write operation, wherein the current does not pass through the at least one conductor or circuit for at least a majority of a time of illumination. Additional embodiments are also presented.