Magnetic Properties of Amorphous Heisenberg Ferromagnet with Random Anisotropy

摘要

Magnetization, susceptibility, and the critical temperature for a spin one amorphous Heisenberg ferromagnet with random local anisotropy are calculated in molecular field approximation for the exchange interaction. The effects of random fluctuations of the magnitude of the local anisotropy about its crystalline value are studied for various probaility distributions. It is found that for a given randomness, measured in terms of the root mean square fluctuation of the magnitude of the local anisotropy, the magnetization and the critical temperature depend more on the range, defined as the magnitude of the maximum value of the fluctuation from its mean value, than the shape of the probability distribution function. The effect of randomness decreases as the crystalline value of the anisotropy increases. Calculation of the susceptibility shows that above the critical temperature, randomness has no effect.