Finite-temperature theory of amorphous metallic magnetism with vector spins

Abstract

A finite temperature theory of amorphous metallic magnetism which takes into account vector spins is developed to study noncollinear magnetism in amorphous Fe. This theory is based on the functional integral method for thermal spin fluctuations and the distribution function method for local magnetic moments with structural disorder. The numerical results at 35 K show up the existence of an isotropic spin-glass in amorphous Fe. When the d electron number n d is increased, the spin-glass changes toa noncollinear ferromagnet at n d = 7.40 and finally to a collinear ferromagnet beyond n d = 7.47.