THEORY OF AMORPHOUS METALLIC MAGNETISM WITH SELF-CONSISTENT AMPLITUDEFLUCTUATIONS AND ITS APPLICATION TO AMORPHOUS FE

A finite-temperature theory of amorphous metallic magnetism has been p roposed on the basis of the distribution-function method and the funct ional-integral technique. It improves the previous theory, and describ es self-consistently the amplitude fluctuations of local magnetic mome nts on the nearest-neighbor shell by means of the distribution functio n of two variables, the local moment, and the local bandwidth paramete r on the same site. Application of the theory to amorphous transition metals around Fe shows that the improved theory reduces the ferromagne tism, smoothes the d-electron number dependence of the spin-glass orde r parameter, and narrows the reentrant spin-glass region. Qualitative features of the magnetic phase diagram, however, is shown to be unchan ged. The present theory supports the existence of spin glass in amorph ous Fe.