Patent classifications
G11B7/1263
Determining instability zones of a laser of a heat-assisted magnetic recording head
Stability or instability zones are determined for ambient temperatures and one or more operational parameters applied to a heat-assisted magnetic recording head. Operations within the stability or instability zones resulting in respective stable or unstable operation of a laser of the recording head. During operation of the recording head, it is determining that a current ambient temperature and currently applied values of the one or more operational parameters are at or near one of the instability zones, and a write operation of the recording head is modified in response.
LASER CALIBRATION USING TEMPERATURE COMPENSATION BASED ON EFFICIENCY FOR HEAT-ASSISTED MAGNETIC RECORDING
A method includes generating, during manufacture of a heat-assisted magnetic recording (HAMR) disk drive, a temperature compensation equation for a compensation factor using initial operating currents supplied to a laser diode of the disk drive at different initial operating temperatures and an efficiency value based on the initial operating temperatures. The operating currents are representative of currents for recording data to or erasing data from a magnetic recording medium. The temperature compensation equation is stored in the disk drive. A subsequent efficiency value is determined based on at least one of the initial operating temperatures and an operating temperature differing from the initial operating temperatures. An updated compensation factor at the operating temperature is determined during field operation using the temperature compensation equation and the subsequent efficiency value. An updated operating current is calculated using the updated compensation factor and the operating temperature. A current supplied to the laser diode for a subsequent write operation is adjusted to the updated operating current.
DETERMINING INSTABILITY ZONES OF A LASER OF A HEAT-ASSISTED MAGNETIC RECORDING HEAD
Stability or instability zones are determined for ambient temperatures and one or more operational parameters applied to a heat-assisted magnetic recording head. Operations within the stability or instability zones resulting in respective stable or unstable operation of a laser of the recording head. During operation of the recording head, it is determining that a current ambient temperature and currently applied values of the one or more operational parameters are at or near one of the instability zones, and a write operation of the recording head is modified in response.
DETERMINING INSTABILITY ZONES OF A LASER OF A HEAT-ASSISTED MAGNETIC RECORDING HEAD
Stability or instability zones are determined for ambient temperatures and one or more operational parameters applied to a heat-assisted magnetic recording head. Operations within the stability or instability zones resulting in respective stable or unstable operation of a laser of the recording head. During operation of the recording head, it is determining that a current ambient temperature and currently applied values of the one or more operational parameters are at or near one of the instability zones, and a write operation of the recording head is modified in response.
THERMAL MANAGEMENT OF LASER DIODE MODE HOPPING FOR HEAT ASSISTED MEDIA RECORDING
A method and apparatus provide for determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording, comparing the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current, and determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current.
THERMAL MANAGEMENT OF LASER DIODE MODE HOPPING FOR HEAT ASSISTED MEDIA RECORDING
A method and apparatus provide for determining a temperature at a junction of a laser diode when the laser diode is operated in a lasing state that facilitates heat-assisted magnetic recording, comparing the junction temperature and an injection current supplied during the lasing state to stored combinations of junction temperature and injection current, and determining a likelihood of mode hopping occurring for the laser diode during the lasing state based on the comparison to stored combinations of junction temperature and injection current.
HEAT-ASSISTED MAGNETIC RECORDING DEVICE INCORPORATING LASER DIODE TEMPERATURE CONTROL USING COMMON-MODE VOLTAGE
An apparatus comprises a slider configured to facilitate heat assisted magnetic recording. The slider comprises a plurality of bond pads including a first electrical bond pad, a second electrical bond pad, and a ground pad. A laser diode comprises an anode coupled to the first electrical bond pad and a cathode coupled to the second electrical bond pad. The laser diode is operable in a non-lasing state and a lasing state. A heater is coupled between the ground pad and at least one of the anode and cathode of the laser diode. The heater is configured to generate heat for heating the laser diode during the non-lasing state and the lasing state.
HEAT-ASSISTED MAGNETIC RECORDING DEVICE INCORPORATING LASER DIODE TEMPERATURE CONTROL USING COMMON-MODE VOLTAGE
An apparatus comprises a slider configured to facilitate heat assisted magnetic recording. The slider comprises a plurality of bond pads including a first electrical bond pad, a second electrical bond pad, and a ground pad. A laser diode comprises an anode coupled to the first electrical bond pad and a cathode coupled to the second electrical bond pad. The laser diode is operable in a non-lasing state and a lasing state. A heater is coupled between the ground pad and at least one of the anode and cathode of the laser diode. The heater is configured to generate heat for heating the laser diode during the non-lasing state and the lasing state.
ON WAFER LASER STABILITY CONTROL FOR HEAT-ASSISTED MAGNETIC RECORDING
An apparatus includes a substrate. A laser is formed on a non-self supporting structure and bonded to the substrate. A waveguide is deposited proximate the laser. The waveguide is configured to communicate light from the laser to a near-field transducer that directs energy resulting from plasmonic excitation to a recording medium. A light detector is configured to detect an amount of light. At least one laser heater is disposed proximate the laser. A controller is configured to control current supplied to the at least one heater based on the detected amount of light.
Optical storage system divider based draw verification with high frequency writing strategy pattern
An optical storage system includes an optical head configured to split a light beam into a higher power main beam and at least one lower power side beam. The optical storage system also includes a controller configured to alter an optical medium, via modulation of the higher power main beam according to a writing strategy waveform that defines at least n pulses for every n bits of data to be written to the medium, while processing a first signal resulting from the at least one lower power side beam being reflected from the medium and a second signal indicative of the writing strategy waveform to remove noise from the first signal caused by the higher power main beam to generate output indicative of the data directly after writing.