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A scaling technique is developed to predict micromagnetic properties of magnetic materials subject to thermal fluctuations over long time scales. This theory, based on the equivalence of time and temperature for thermally activated processes, is tested by predicting hysteresis loops for two different thin film magnetic recording media. A comparison to directly calculated values and to experimental hysteresis loop results shows that important features such as the coercivity are predicted with less than 1% error.

A comprehensive analysis of the areal density potential of bit-patterned media recording shows that the recording performance is dominated by written-in errors. The statistical fluctuations of the magnetic properties and the locations of the individual bits lead to error probabilities so that some dots are either not recorded at all or cannot be recorded in the time window necessary to ensure synchronized writing. The highest areal densities are obtained with a combination of a pole head, a soft magnetic underlayer, and a storage medium of the composite type. Areal density scenarios of up to 5Tbits∕in.2 are analyzed.