Patent ID: 8787124

Claim:
A system for extracting a Curie temperature distribution in a heat assisted magnetic recording medium, the system comprising: a magnetic recording medium; a spindle configured to rotate the medium; a magnet adjacent to the medium and configured to generate a magnetic field; a laser configured to direct light on the medium; a light detector configured to detect light reflected from the medium; and a processor coupled to the spindle, the magnet, the laser, and the light detector, the processor configured to: saturate the medium by causing the laser to direct light on the medium and causing the magnet to generate a magnetic field on the medium; cause the magnet to remove the magnetic field on the medium; write to the medium by causing the laser to direct light on the medium; record measurements of light reflected from the medium made by the light detector; convert the measurements of reflected light into measurements of remanent thermal magnetization; and extract the Curie temperature distribution from the measurements of remanent thermal magnetization.