MASTER EQUATION APPROACH TO ANHYSTERESIS OF NONINTERACTING PARTICLES

Hysteresis in an array of thermally relaxing, aligned, noninteracting uniaxial particles driven by a periodic applied field with an attenuating amplitude and a dc bias is studied. The asymptotic state reached after the ac component attenuated to zero has the characteristics of anhysteretic magnetization. The convergence of the solution is studied, the anhysteresis curve is shown to lie below the curve of the equilibrium magnetization, a heuristic formula for the initial anhysteretic susceptibility is proposed, and the effects of interparticle interactions is discussed.