EXISTENCE OF THE SPIN-GLASS STATE IN AMORPHOUS FE

The volume dependence of magnetic properties in amorphous Fe has been calculated on the basis of the finite-temperature theory of amorphous metallic magnetism which self-consistently determines the distribution of local magnetic moments. The calculated magnetic phase diagram on t he T-V plane and magnetization-vs-volume curve show the existence of t he spin-glass state in a wide range of volume (10.50 angstrom3 less th an or similar V less than or similar 12.5 angstrom3) after disappearan ce of ferromagnetism. The results verify our previous conclusion of th e spin-glass state in amorphous Fe, which is expected from the experim ental data of Fe-rich amorphous alloys containing early transition met als and rare-earth metals, but disagree with those obtained from the s upercell approaches in the ground-state electronic structure calculati ons. It is shown that the nonlinear magnetic couplings between the nea rest-neighbor Fe local moments and the local environment effects on th e amplitude of Fe local moments via structural disorder lead to the sp in-glass state in the weak magnetic region, while the volume expansion develops the ferromagnetic couplings and therefore the ferromagnetism .