Patent ID: 8767327

Claim:
A method for writing data in a heat-assisted magnetic recording (HAMR) disk drive having a read head, a write head for generating a magnetic field, a laser, a transducer coupled to the laser for generating heat, and a magnetic recording disk having a recording layer, the recording layer having a plurality of data tracks, a plurality of angularly spaced servo sectors extending generally radially across the tracks, a laser power gap adjacent each servo sector, and a plurality of data sectors in the tracks and located between the laser power gaps and the servo sectors, the disk being rotatable past the write head and the transducer, the method comprising: receiving new data to be written to the data sectors; determining which data sectors are to be written with the new data; determining from the data sectors to be written the servo sector preceding the first data sector to be written and the servo sector following the last data sector to be written; acquiring old data from data sectors between said first and last servo sectors; combining the old data with the new data; turning on laser power to generate heat with the transducer when the transducer is aligned with the laser power gap adjacent said first servo sector; generating a magnetic field with the write head; and writing the combined old and new data in all of the data sectors successively between said first and last servo sectors by simultaneously heating the recording layer and applying a magnetic field to the recording layer as the disk rotates.