| Since the introduction of the world's first magnetic recording hard drive in 1956 the areal density has increased by more than eight orders of magnitude. Today as laboratory demonstration approach 150 Gb/inch 2, fundamental physical barriers threaten to slow or even stop the growth in areal density. For growth to continue, new technologies and recording methodologies are required. One potential new technology is heat assisted magnetic recording (HAMR). In HAMR the medium is heated with a laser during the recording process to reduce the coercivity. This allows thermally stable, high anisotropy materials to be used in the fabrication of the recording medium which could otherwise not be used in a conventional recording system.; In this thesis the HAMR process is explored both theoretically and experimentally. The analytic Williams Comstock recording model is modified to include thermal gradients and the thermal properties of the recording medium. The newly developed model predicts a transition parameter that is dependent not only on the thermal gradients but also on the thermal properties of the medium and transition curvature. It is found that if the system is properly aligned and the recording temperature and applied write field are correctly optimized, an optimal PW50 can be achieved which is slightly smaller than what is possible by using a conventional recording system. In addition a HAMR spin stand is developed and is used to experimentally verify features predicted by the model such as transition curvature, optimal alignment and PW50 trends. |
