Thermal management of laser diode mode hopping for heat assisted media recording
AssigneeSeagate Technology LLC
InventorsKarim Tatah, Mourad Benakli, James Gary Wessel
Life of this patent
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Abstract
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.
Claims20
An apparatus, comprising:
- a slider and a laser diode configured to facilitate heat assisted magnetic recording (HAMR), the slider comprising:
- a read element and a write element respectively situated at an air bearing surface (ABS) of the slider;
- a near-field transducer (NFT) situated at the ABS proximate the write element;
- an optical waveguide configured to couple light from the laser diode to the NFT;
- a temperature sensing arrangement configured to determine a temperature at a junction of the laser diode;
- and
- a heater arrangement configured to heat the junction of the laser diode;
- and
- a controller coupled to the slider and the laser diode, the controller comprising:
- a laser control coupled to the laser diode and configured to control operation of the laser diode;
- and
- a heater control coupled to the heater arrangement and configured to control operation of the heater arrangement, the heater control configured to control the heater arrangement to heat the laser diode junction during a non-lasing state of the laser diode or during at least a portion of the non-lasing state and at least a portion of the lasing state of the laser diode.
An apparatus, comprising:
- a slider and a laser diode configured to facilitate heat assisted magnetic recording (HAMR), the slider comprising:
- a read element and a write element respectively situated at an air bearing surface (ABS) of the slider;
- a near-field transducer (NFT) situated at the ABS proximate the write element;
- an optical waveguide configured to couple light from the laser diode to the NFT;
- a temperature sensing arrangement configured to determine a temperature at a junction of the laser diode;
- and
- a heater arrangement configured to heat the junction of the laser diode;
- and
- a controller coupled to the slider and the laser diode, the controller comprising:
- a laser control coupled to the laser diode and configured to control operation of the laser diode;
- a heater control coupled to the heater arrangement and configured to control operation of the heater arrangement, the heater control configured to control the heater arrangement to heat the laser diode junction during a non-lasing state of the laser diode or during at least a portion of the non-lasing state and at least a portion of the lasing state of the laser diode;
- and
- a processor coupled to the controller and configured to determine a likelihood of mode hopping occurring for the laser diode during the lasing state based on a comparison of the junction temperature of the laser diode and an injection current relative to stored combinations of junction temperature and injection current.
Dependencies are inferred from the claim text.