A heat-assisted magnetic recording head is moved relative to a magnetic recording medium. The medium comprises a plurality of sectors. The sectors define a plurality of sector groups distributed around a circumference of the medium. The sectors of each sector group are written using different operational currents supplied to a laser diode of the head such that at least one sector from each sector group is written using one of the different operational currents. For each of the different operational currents, an average write performance metric is calculated for all sectors written at each of the different operational currents. A particular operational current of the different operational currents is determined that results in a best average write performance metric.

A combination of a semiconductor member and a metal member is selected appropriately from a view point of increasing an enhancement factor of a near-field light. A device (1) has a semiconductor member (101) and a metal member (102), a near-field light is generated at the metal member when an energy is supplied to the semiconductor member, the metal member is made of an alloy including a first metal and a second metal, a condition of Rm1<Rs<Rm2 is satisfied, wherein a resonance wavelength of the first metal is Rm1, a resonance wavelength of the second metal is Rm2, and a resonance wavelength of the semiconductor member is Rs.

An optically shielded TAMR (thermally assisted magnetic recording) write head has a metal waveguide blocker formed against a distal end of a waveguide and a pair of symmetrically disposed optical side shields formed to either side of a plasmon generator formed above the waveguide. The waveguide focuses optical radiation on the adjacent plasmon generator where it excites plasmon modes that heat the recording medium with near-field energy and the waveguide blocker prevents excess optical radiation from blurring the spot on the recording region. The optical side shields further restrict loosely coupled optical radiation from reaching the recording region and blurring the optical spot and improves down-track and cross-track thermal gradients.

A first waveguide portion receives light from an energy source in a fundamental transverse electric (TE.sub.00) mode. A mode converter converts a portion of the light to higher-order transverse electric (TE.sub.10) mode. A second waveguide portion receives the light at the TE.sub.10 mode and delivers the light to a near-field transducer that heats a recording medium in response thereto. An optical spatial mode filter prevents remnant light in the TE.sub.00 mode from affecting the recording medium while passing the light at the TE.sub.10 mode.

Light is directed from a light source at a coupling surface of a slider into a delivery waveguide of the slider. The delivery waveguide couples a first portion of the light into a near-field transducer at a media-facing surface. A second portion of the light is coupled into a splitter waveguide. The second portion of light is detected to perform an active alignment of the light source on the slider.

An apparatus includes a first waveguide core extending along a light-propagation direction and configured to receive light from a light source at a combined transverse electric (TE) mode and a transverse magnetic (TM) mode. A second waveguide core is spaced apart from the first waveguide core and is configured to couple light at a TM mode to the second waveguide core. A near-field transducer (NFT) is disposed at a media-facing surface of a write head, the NFT receiving the light from the first waveguide core or the second waveguide core and heating a magnetic recording medium in response thereto.

A slider configured for heat-assisted magnetic recording comprises a magnetic writer, a near-field transducer, and an optical waveguide coupling the near-field transducer to a light source. The writer is situated proximate the near-field transducer at an air bearing surface of the slider and comprises a first return pole, a second return pole, and a write pole situated between and spaced apart from the first return pole and the second return pole. A structural element is situated at or near the air bearing surface between the write pole and one of the first and second return poles. The structural element comprises a cavity. A thermal sensor is disposed in the cavity. The thermal sensor is configured for sensing contact between the slider and a magnetic recording medium, asperities of the medium, and output optical power of the light source.

A circuit includes a light source, a sensor, and a switch. The sensor measures output of the light source and provides an electrical signal to a feedback loop that is indicative of the measured output of the light source. The switch is positioned in the feedback loop and is movable between a first position and a second position depending upon whether the feedback loop is operating in a first mode of operation or a second mode of operation. During the first mode of operation the output of the feedback loop adjusts at least one operating parameter of the light source responsive to the electrical signal. During the second mode of operation the output of the feedback loop does not adjust the at least one operating parameter of the light source responsive to the electrical signal.

Methods that include depositing a first layer over the entire surface of a structure, the structure having a magnetic reader and a magnetic writer, wherein the magnetic reader and the magnetic writer are positioned adjacent to each other on a substrate and the magnetic writer includes a near field transducer (NFT); depositing a second layer over the entire surface of the first layer; depositing a photoresist material layer over the entire surface of the second layer, the photoresist material layer having a bottom surface in contact with the second layer and an opposing top surface; exposing the photoresist material layer to radiation through the bottom surface of the photoresist material layer via the NFT to form a first exposed region; and exposing the photoresist material layer to radiation through the top surface of the photoresist material layer to form a second exposed region.

An apparatus includes an apparatus comprising a slider. The slider comprises a substrate comprising a media-facing surface, a first side surface perpendicular to the media-facing surface, and a second side surface opposite the first side surface. A heat sink layer is formed proximate to and thermally coupled to the first side surface of the substrate. A write transducer comprises a waveguide core that at least partially extends from the top surface to the media-facing surface. The waveguide core is formed proximate to and thermally coupled to the heat sink layer. A read transducer is formed proximate to the write transducer such that the read transducer is closer to a trailing edge of the slider than the write transducer.