Comment on "Magnetism inAu82.5Fe17.5"

Abstract

Low-field magnetization in parallel and perpendicular geometries, Mössbauer spectroscopy, and small-angle neutron scattering data, carried out on the same samples of amorphous reentrant spin-glass alloys ${\left({\mathrm{Fe}}_x{\mathrm{Cr}}_{1-x}\right)}_{75}{\mathrm{P}}_{15}{\mathrm{C}}_{10}$ suggest a true phase transition with cooperative phenomena at $T_c$ and not a simple deviation from the Langevin paramagnetism as suggested by Rakers and Beck [Phys. Rev. B 36, 8622 (1987)] in ${\mathrm{Au}}_{82.5}$ ${\mathrm{Fe}}_{17.5}$ alloy. A departure from conventional ferromagnetism is found in the small size of the domains, which could be some thousands of angstroms.