Positive laser bias electrical control architecture for dark laser heating in heat assisted magnetic recording

A data storage device comprising:

• a disk;
• a read/write head configured to read data from and write data to the disk;
• a laser diode coupled to a near field transducer (NFT) configured to heat an area of the disk near the read/write head;
• an asymmetric laser diode driver configured to drive the laser diode, wherein the asymmetric laser diode driver comprises:
• a first current mirror for controlling at least an overshoot amplitude for positive or rising transitions of a positive bias current applied to the laser diode;
• and
• a second current mirror for controlling at least an overshoot amplitude for negative or falling transitions of a negative bias current applied to the laser diode;
• and
• one or more processing devices or components configured, individually or in combination, to:
• preheat the laser diode to a target temperature, wherein the preheating comprises:
• generating at least one bias pulse conforming to one or more tunable parameters, based at least in part on the target temperature;
• and
• applying, using the asymmetric laser diode driver, the at least one bias pulse to the laser diode such that no optical response is produced by the laser diode;
• and
• initiate a write operation for writing data to the disk.

A method for operating a data storage device configured for heat-assisted magnetic recording using a laser diode, the method comprising:

• preheating the laser diode to a target temperature, wherein the preheating comprises:
• generating, based at least in part on the target temperature, at least one bias pulse conforming to a plurality of parameters, the plurality of tunable parameters including one or more amplitude parameters, wherein the one or more amplitude parameters comprise one or more of:
• (1) a first laser diode bias current (IP) greater than a lasing threshold current, (2) a second laser diode bias current (IN) lower than the lasing threshold current, (3) a first duration (TPD), and (4) a second duration (TND);
• and
• applying, using an asymmetric laser diode driver, the at least one bias pulse to the laser diode such that no optical response is produced by the laser diode;
• and
• initiating a write operation for writing data to a disk of the data storage device.

One or processing devices comprising:

• means for preheating a laser diode of a data storage device to a target temperature, wherein the data storage device is configured for heat-assisted magnetic recording using the laser diode, and wherein the means for preheating comprises:
• means for generating, based at least in part on the target temperature, at least one bias pulse conforming to a plurality of tunable parameters, the plurality of tunable parameters including one or more amplitude parameters, wherein the one or more amplitude parameters comprise one or more of:
• (1) a first laser diode bias current (IP) greater than a lasing threshold current, (2) a second laser diode bias current (IN) lower than the lasing threshold current, (3) a first duration (TPD), and (4) a second duration (TND);
• and
• means for applying the at least one bias pulse to the laser diode such that no optical response is produced by the laser diode;
• and
• means for initiating a write operation for writing data to a disk of the data storage device.

A data storage device comprising:

• a disk;
• a read/write head configured to read data from and write data to the disk;
• a laser diode (LD) coupled to a near field transducer (NFT) configured to heat an area of the disk near the read/write head;
• an asymmetric LD driver configured to drive the LD, wherein the asymmetric LD driver comprises an asymmetric Bipolar Complementary Metal-Oxide Semiconductor (BiCMOS) driver;
• and
• one or more processing devices or components configured, individually or in combination, to:
• preheat the laser diode to a target temperature, wherein the preheating comprises:
• generating at least one bias pulse conforming to one or more tunable parameters, based at least in part on the target temperature;
• and
• applying, using the asymmetric LD driver, the at least one bias pulse to the laser diode such that no optical response is produced by the laser diode;
• and
• initiate a write operation for writing data to the disk.