Angular variation of coercivity in thin-film media by micromagnetic model

A computer micromagnetic simulation model is employed to study the angular variation of coercivity (out of plane) in thin-film media. Each grain of the film is uniformly magnetized and switches coherently according to the S-W model. The M-H hysteresis loops for applied fields at different angles to the film plane are obtained for various magnetostatic interaction parameters, quantum exchange constants, and easy axis distributions. The angular variation of the coercivity curve exhibits a peak if there is magnetostatic interaction among the grains and qualitatively follows the experimental results well. The peak in the angular variation of coercivity is seen to result from the demagnetizing field. The rotational hysteresis process is also investigated by means of this model.<
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