A storage device includes a storage controller configured to operate a heat-assisted magnetic recording head to write data to a band of consecutive data tracks in a consecutive track order while selectively alternating a power level of the heat source when writing to some data tracks of the band.

A waveguide core extends from an input coupler towards a media-facing surface of a read/write head. A cap is located between a terminating end of the waveguide core and the media-facing surface. The cap is formed of a high index of refraction, high-corrosion resistant material that is different than a material used to form the waveguide core. A near-field transducer is proximate the cap in a down-track direction. A head overcoat on the media-facing surface covers the cap.

An apparatus comprises a slider configured for heat-assisted magnetic coupled to a controller. The slider comprises a writer, a heater, a near-field transducer, and an optical waveguide for communicating light from a laser diode to the near-field transducer. The controller is configured to set a target pre-write clearance of the slider prior to performing a write operation, set a target write clearance of the slider for performing the write operation, and determine a difference between the target pre-write and write clearances to define a target pre-write clearance offset. The controller is also configured to measure, for a plurality of different target pre-write clearance offsets, a writability metric for the slider while sweeping a laser diode current, and adjust the target pre-write clearance offset so that the writability metric reaches a predetermined threshold. The controller is further configured to perform subsequent write operations using the adjusted target pre-write clearance offset.

An apparatus is disclosed. The apparatus includes a storage layer, a thermal exchange control layer disposed over the storage layer, and a write layer disposed over the thermal exchange control layer. A Curie temperature of the thermal exchange control layer is lower than a Curie temperature of the storage layer. The Curie temperature of the thermal exchange control layer is lower than a Curie temperature of the write layer.

Methods and apparatuses for detecting mode hopping in a laser diode or other optical energy source in heat-assisted magnetic recording. An output power of the laser diode or other optical energy source is measured and the output power is differentiated over time to determine a rate of change. If it is determined that the rate of change exceeds a threshold value, a fault signal is asserted indicating a potential mode hopping event.

A slider is configured for heat-assisted magnetic recording and comprises an NFT and a transparent thermocouple configured to produce a signal indicative of temperature at the NFT. A detector can be coupled to the thermocouple and configured to detect one or both of spacing changes and contact between the slider and a magnetic recording medium.

A slider configured for heat-assisted magnetic recording comprises an air bearing surface (ABS), a writer, and a close point of the writer. A plurality of heat producing or dissipating components are situated a predetermined distance from a vertical plane that is normal to the ABS and aligned with the close point. A location of the writer close point remains substantially consistent irrespective of which of the plurality of heat producing or dissipating components are energized.

A slider includes a slot waveguide configured to receive energy from an input surface. The slot waveguide has first and second high-index regions surrounding a middle region that extends along a light propagation direction. The middle region has a refractive index less than that of the first and second high index regions. A near-field transducer is at an output portion of the middle region at media-facing surface. The near-field transducer has first and second plates parallel to the media-facing surface with a gap therebetween. An active laser region has a front facet optically coupled to the input surface of the slider. A reflective back facet of the laser and the near-field transducer define a single optical resonator.

An apparatus comprises a slider having a trailing edge and a leading edge. A laser diode unit comprises a submount and a laser diode mounted to the submount. The submount includes a mounting surface affixed to a first surface of the slider at the trailing edge such that a first surface of the submount faces toward the leading edge of the slider. A thermally conductive material covers the first surface of the submount and at least a portion of the first surface of the slider. The thermally conductive material serves as a thermal conduction pathway between the submount and the slider.

A method and apparatus are directed to providing relative movement between a slider configured for heat-assisted magnetic recording and a magnetic recording medium, and causing protrusion of a portion of an air bearing surface (ABS) of the slider in response to activating at least a laser source while maintaining spacing between the protrusion and the medium. A magnitude of at least a portion of the protrusion is measured while maintaining spacing between the protrusion and the medium.