STATISTICAL-MECHANICS OF A NONLINEAR RELAXATION PROCESS .2. DYNAMIC PROPERTIES

The dynamical properties of a semiclassical model of spin relaxation are carefully studied with the help of computer simulation. It is shown that, as an effect of the reaction field, the relaxation time as a function of temperature ranges from an Arrhenius-like behavior at weak temperatures to a linear power-law behavior at high temperatures. It is also shown that a fairly accurate theoretical prediction of the relaxation time can be obtained in both the low- and high-temperature limit. In the latter regime a simple factorization prescription, although leading to small deviations from the exact equilibrium value for the spin components, is shown to provide the most accurate predictions.