A slider of a heat-assisted recording head comprises electrical bond pads coupled to bias sources and a ground pad, an air bearing surface, and a waveguide configured to receive light from a laser source. A contact sensor proximate the air bearing surface is coupled between a first bond pad and a second bond pad. A bolometer is coupled to a reference thermal sensor. The bolometer is situated at a slider location that receives at least some of the light communicated along the waveguide. The reference thermal sensor is situated at a slider location unexposed to the light communicated along the waveguide. The bolometer and reference thermal sensor are coupled between the first and second bond pads and in parallel with the contact sensor. A ground connection is coupled to the ground pad and at a connection between the bolometer and the reference thermal sensor.

A data storage device is disclosed comprising a head actuated over a disk, wherein the head comprises a laser configured to heat the disk while writing data to the disk. At least four different laser powers are applied to the laser and a fly height of the head over the disk is measured at each laser power. A lasing threshold power for the laser is detected based on the measured fly heights.

A data storage device (DSD) includes a base-deck, a disc above the base-deck, and a shaft extending perpendicular from the base-deck. The DSD also includes a head stack assembly (HSA) including a head gimbal assembly having a load beam and a head at a first end of the HSA. The head interacts with a surface of the disc. The HSA also includes a second end movably mounted on the shaft. The DSD additionally includes an elevator that linearly moves the HSA along the shaft to adjust a distance between the load beam and the surface of the disc in response to receiving a feedback signal associated with the interaction of the head with the surface of the disc. The feedback signal is one of a plurality of feedback signals employed by the elevator to adjust the distance between the load beam and the surface of the disc.

A method of operating an HDD having a slider-mounted read/write head that is configured for dynamic fly-height operation (DFH) and includes at least one head-disk interference sensor (HDIs). By operating the DFH to lower the head and subjecting the HDIs signal to a power-law enhancement, a consistent and accurate determination of the touchdown power (TDP) can be obtained. Combining absolute TDP determination with a method for measuring relative changes of FH, an absolute determination of FH can be determined.

Apparatus and method for heat assisted magnetic recording (HAMR). In some embodiments, a write element has a magnetic write coil that writes a magnetic pattern to a recording layer of a data recording surface. A light delivery mechanism imparts heat in the form of electromagnetic energy to the data recording layer during operation of the write element. A radiation detector detects radiation power emitting from the recording layer responsive to the operation of the light delivery mechanism. A control circuit determines a direct temperature of the recording layer responsive to the detected radiation power, and as necessary, adjusts a power input to the light delivery mechanism responsive to the determined temperature. The radiation detector may be an infrared photodetector with a graphene-based detection layer. The photodetector may be disposed between a write pole and a return pole of the write element.

Described are heat assisted magnetic read-write heads that include a coupler, a waveguide, a transducer, and appurtenant structures.

A slider of a heat-assisted recording head comprises electrical bond pads coupled to bias sources and a ground pad, an air bearing surface, and a waveguide configured to receive light from a laser source. A contact sensor proximate the air bearing surface is coupled between a first bond pad and a second bond pad. A bolometer is coupled to a reference thermal sensor. The bolometer is situated at a slider location that receives at least some of the light communicated along the waveguide. The reference thermal sensor is situated at a slider location unexposed to the light communicated along the waveguide. The bolometer and reference thermal sensor are coupled between the first and second bond pads and in parallel with the contact sensor. A ground connection is coupled to the ground pad and at a connection between the bolometer and the reference thermal sensor.

The present application provides a transducer head comprising a laser source configured to heat a target storage medium surface, and a thermal sensor configured to detect a defect on the target storage medium surface. The present application also provides a method comprising heating a target storage medium surface with an energy source configured in a transducer head to irradiate the target storage medium surface, and detecting a defect on the target storage medium surface using a thermal sensor configured in the transducer head. Other implementations are also described and recited herein.

An apparatus comprises a slider having an air-bearing surface (ABS), a write pole at or near the ABS, and a reader at or near the ABS and connected to a pair of reader bond pads of the slider. A near-field transducer (NFT) is formed on the slider at or near the ABS, and an optical waveguide is formed in the slider and configured to receive light from a laser source. A sensor is situated proximal of the write pole at a location within the slider that receives at least some of the light communicated along the waveguide. The sensor may be electrically coupled to the reader bond pads in parallel with the reader, and configured to generate a signal indicative of output optical power of the laser source.

An apparatus comprises a slider and an optical waveguide formed in the slider and configured to receive light from a laser source. A near-field transducer (NFT) is formed on the slider at or near an air bearing surface (ABS) of the slider and optically coupled to the waveguide. A bolometric sensor is positioned proximate the NFT and exposed to at least some of the light. The bolometric sensor is configured to detect changes in output optical power of the laser source and contact between the slider and a magnetic recording medium.