Abstract: A hard disk drive (HDD) includes a heat-assisted magnetic recording (HAMR) head. The HAMR head includes one or more features comprising a laser device that is a heterogeneous integrated epitaxial grown GaAS laser. The laser device couples directly with a waveguide that transfers the electromagnetic radiation generated by the laser device to a near field transducer. The device includes an N-doped layer for coupling the output of the GaAs active layer to the waveguide.

Abstract: A heat-assisted magnetic recording head includes a laser, a near-field transducer, a primary waveguide, a secondary waveguide, and a photodiode. The laser is configured to emit electromagnetic radiation. The near-field transducer is configured to focus and emit an optical near-field. The primary waveguide configured to receive the electromagnetic radiation and propagate the electromagnetic radiation toward and proximal to the near-field transducer. The secondary waveguide configured to receive a portion of the electromagnetic radiation from the primary waveguide. The photodiode configured to receive the portion of the electromagnetic radiation from the secondary waveguide and emit a signal that represents a magnitude of the electromagnetic radiation that the laser emits.

Abstract: A heat-assisted magnetic recording head includes a laser, a near-field transducer, a primary waveguide, a secondary waveguide, and a photodiode. The laser is configured to emit electromagnetic radiation. The near-field transducer is configured to focus and emit an optical near-field. The primary waveguide configured to receive the electromagnetic radiation and propagate the electromagnetic radiation toward and proximal to the near-field transducer. The secondary waveguide configured to receive a portion of the electromagnetic radiation from the primary waveguide. The photodiode configured to receive the portion of the electromagnetic radiation from the secondary waveguide and emit a signal that represents a magnitude of the electromagnetic radiation that the laser emits.

Abstract: A heat-assisted magnetic recording head includes a laser, a near-field transducer, a primary waveguide, a secondary waveguide, and a photodiode. The laser is configured to emit electromagnetic radiation. The near-field transducer is configured to focus and emit an optical near-field. The primary waveguide configured to receive the electromagnetic radiation and propagate the electromagnetic radiation toward and proximal to the near-field transducer. The secondary waveguide configured to receive a portion of the electromagnetic radiation from the primary waveguide. The photodiode configured to receive the portion of the electromagnetic radiation from the secondary waveguide and emit a signal that represents a magnitude of the electromagnetic radiation that the laser emits.

Abstract: An external cavity laser of a recording head includes a channel waveguide that delivers light towards a media-facing surface of the recording head. The laser includes an externally mounted part with an active region having a longitudinal axis corresponding to a light propagation direction of the channel waveguide. The externally mounted part has a reflective back facet and anti-reflective front facet. The laser includes a near-field transducer at an end of the channel waveguide proximate the media facing surface. The reflective back facet and the near-field transducer define a resonator of the external cavity laser.

Abstract: In a mailbox delivery alert system, a closure abutment secured to an outer end of an arm is pushed by pivoting a mailbox closure from a closed position to an open position, and the arm is moveably mounted relative to a flag intermediate its ends for movement parallel to and at non-parallel angles to the flag height. The moving arm pushes an arm abutment secured to an inner end of the arm against the flag intermediate its ends, with the arm abutment pivoting the flag from a home position to an alert position.

Abstract: In a mailbox delivery alert system, a closure abutment secured to an outer end of an arm is pushed by pivoting a mailbox closure from a closed position to an open position, and the arm is moveably mounted relative to a flag intermediate its ends for movement parallel to and at non-parallel angles to the flag height. The moving arm pushes an arm abutment secured to an inner end of the arm against the flag intermediate its ends, with the arm abutment pivoting the flag from a home position to an alert position.

Abstract: A recording head includes an external cavity laser with an externally mounted part having an active region. The external cavity laser also includes a channel waveguide that delivers light towards a media-facing surface. A near-field transducer functions as a reflector, either alone or in combination with a Bragg grating in the channel waveguide. A reflective back facet of the externally mounted part and the reflector define a resonator of the external cavity laser.

Abstract: A folded lasing cavity comprises at least one bend. The folded lasing cavity is disposed on and configured to emit light along a substrate-parallel plane. An etched facet is on an emitting end of the folded lasing cavity and an etched mirror is on another end of the folding lasing cavity. An etched shaping mirror redirects light received from the etched facet in a direction normal to the substrate-parallel plane.

Abstract: A storage-type water heater including a tank for supporting water to be heated, a first heating element, a first relay connected to the first heating element, a second heating element, a second relay connected to the second heating element, and a controller for selectively operating the first relay and the second relay. The controller includes instructions for selecting a mode from at least, a no-sequencing mode, wherein the first relay and the second relay are operated concurrently, and a sequencing mode, wherein the first relay and the second relay are operated sequentially. The controller also operates the first relay to supply power to the first heating element, and operates the second relay to supply power to the second heating element, based on the selected mode.

Abstract: There is provided a method that includes (a) controlling a vibrator to produce an acoustic wave in accordance with a signal that includes (i) an on-time during which a packet of pulses is generated, followed by (ii) an off-time during which no pulses are generated, and thus includes (iii) a frequency component, (b) receiving an electrical representation of the acoustic wave that has been detected from a body of water that is being frozen on a structure, (c) extracting, from the electrical representation, (i) the frequency component, and (ii) a magnitude of the frequency component, (d) recognizing that the magnitude of the frequency component exceeds a threshold value, thus yielding a recognition, and (e) issuing a command to remove the body of water from the structure, in response to the recognition. There is also provided a system that employs the method, and a storage device containing instructions for the method.

Abstract: There is provided a method that includes (a) controlling a vibrator to produce an acoustic wave in accordance with a signal that includes (i) an on-time during which a packet of pulses is generated, followed by (ii) an off-time during which no pulses are generated, and thus includes (iii) a frequency component, (b) receiving an electrical representation of the acoustic wave that has been detected from a body of water that is being frozen on a structure, (c) extracting, from the electrical representation, (i) the frequency component, and (ii) a magnitude of the frequency component, (d) recognizing that the magnitude of the frequency component exceeds a threshold value, thus yielding a recognition, and (e) issuing a command to remove the body of water from the structure, in response to the recognition. There is also provided a system that employs the method, and a storage device containing instructions for the method.

Abstract: An apparatus comprises a first electrical contact, a second electrical contact, and a semiconductor device disposed between the first and second electrical contacts. The semiconductor device comprises a laser diode and a temperature control unit. The laser diode comprises p-type semiconductor material and n-type semiconductor material. The temperature control unit comprises p-type semiconductor material, n-type semiconductor material, and a resistor coupled to the laser diode. One of the p-type semiconductor material and the n-type semiconductor material is shared by the laser diode and the temperature control unit.

Abstract: A folded lasing cavity comprises at least one bend. The folded lasing cavity is disposed on and configured to emit light along a substrate-parallel plane. An etched facet is on an emitting end of the folded lasing cavity and an etched mirror is on another end of the folding lasing cavity. An etched shaping mirror redirects light received from the etched facet in a direction normal to the substrate-parallel plane.

Abstract: A device such as a photo sensor, an optical isolator, and an optical damper is formed via a first process. The device is transfer printed to a waveguide of a read/write head in a second process.

Abstract: A laser is configured to emit light along a substrate-parallel plane along a first surface of the laser. An etched facet is on an emitting end of a lasing cavity and an etched mirror is on another end of the lasing cavity. An etched shaping mirror redirects light received from the etched facet in a direction normal to the substrate-parallel plane. A slider comprises an optical input coupler configured to couple the light from the laser into a waveguide of the slider. At least one protrusion is disposed on the laser and at least one recession is disposed on the slider, the at least one protrusion and the at least one recession configured to align the laser with the slider to allow the light to be coupled into the optical input coupler.

Abstract: A recording head includes a layer of plasmonic metal deposited on a surface of the recording head. One or more non-self-supporting layers of crystalline material are attached to the plasmonic metal, the one or more layers of crystalline materials configured to form an active region of a laser. A waveguide is configured to receive plasmons from the laser and direct the plasmons to a recording medium.

Abstract: A recording head includes a layer of plasmonic metal deposited on a surface of the recording head. One or more non-self-supporting layers of crystalline material are attached to the plasmonic metal, the one or more layers of crystalline materials configured to form an active region of a laser. A waveguide is configured to receive plasmons from the laser and direct the plasmons to a recording medium.

Abstract: A laser diode has a first gain section having a first length and a second gain section having a second length and aligned with the first gain section. The second gain section is aligned with and coupled to the first gain section along a light output direction. The second length is an integer multiple m of the first length, where m is greater than one.

Abstract: A mounting surface of a read/write head is prepared to receive an epitaxial layer. The mounting surface is proximate a waveguide of the read/write head, and the waveguide is configured to receive an optical output from the epitaxial layer. The epitaxial layer is transfer printed on to the mounting surface. The mounting surface maintains a vertical alignment between the optical output and the waveguide. The epitaxial layer is processed to form a laser integrated with the read/write head.