Angular dependence of coercivity for Nd/sub 15/Fe/sub 77/B/sub 8/ in the temperature range from 4.2 to 300 K

Defining the fields B/sub n1/ and B/sub n2/, where the magnetization reversal begins and ends, the simple linear relationship B/sub n2/=aB/sub n1/+b mu /sub 0/M/sub s//cos theta was observed, where a and b are coefficients. Furthermore, from the temperature dependence of the change in magnetic energy Delta E in the system, an activation volume was obtained as a function of temperature. The values are in good agreement with the results obtained from magnetic viscosity measurements. This indicates that magnetization reversal is thermally initiated in a small activation volume.<
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