Magnetic Ordering in Gold-Iron Alloys

摘要: In an attempt to characterize the magnetic ordering in $\mathrm{Au}\mathrm{Fe}$ alloys, systematic studies were made of temperature dependences thermoelectric power $S$ and low-field susceptibility $\ensuremath{\chi}$ for Fe concentrations $C$ from 1 22 at.%. The concentration magnitude maximum $S(T)$ showed transitions clearly related ordering. Data analyses based on molecular field theories indicate existence small regions short-range ferromagnetic order which undergo longrange interactions as is lowered. For $C\ensuremath{\gtrsim}12$ at.%, long-range ferromagnetism dominant. Lower-concentration alloys ($C\ensuremath{\lesssim}12$ at.%) exhibit antiferromagnetism with some properties similar those a spin-glass, but well-defined temperatures characterized by sharp cusps $\ensuremath{\chi}(T)$, negative Curie $\ensuremath{\theta}$ $C=1 \mathrm{and} 2$ These more perfect antiferromagnetic than that expected random alloy or this may be preferred local lattice arrangements these alloys.