Time and temperature dependences of the magnetization reversal in a Co∕Pd multilayer film

The time and temperature dependences of the magnetization reversal have been measured in a high-coercivity Co∕Pd multilayer film characterized by nucleation and domain wall motion. The time and field dependences of magnetic relaxation curves at room temperature were interpreted in terms of an energy barrier that depends linearly on reverse field, suggesting a Sharrock-type [M. P. Sharrock and J. T. McKinney, IEEE Trans. Magn. 17, 3020 (1981)] equation for the time and temperature dependences of coercivity with unity exponent. The sweep rate and temperature dependence of the coercivity were analyzed using the Sharrock equation to obtain the temperature dependence of the intrinsic, short-time coercivity H0 and the zero-field energy barrier E0. A single power law behavior was found for H0 versus the saturation magnetization Ms.