COMPUTER-SIMULATION STUDY OF MAGNETIC-RELAXATION IN ANISOTROPIC MAGNETIC SYSTEMS

We present a computer-simulation study of the effect of the distributi on of energy barriers in an anisotropic magnetic system on the relaxat ion behavior of the magnetization. While the relaxation law for the ma gnetization can be approximated in all cases by a time logarithmic dec ay, the law for the dependence of the magnetic viscosity with temperat ure is found to be quite sensitive to the shape of the distribution of barriers. The low-temperature region for the magnetic viscosity never extrapolates to a positive no-null value. Moreover our computer simul ation results agree reasonably well with some recent relaxation experi ments on highly anisotropic single-domain particles.