Hyperfine fields in metallic glasses

We review recent experimental data obtained on hyperfine fields (hf) in amorphous metallic alloys. We restrict ourselves to magnetically ordered materials. Both the average value and the distribution of the hf are discussed for three different cases. First, we summarize the hf data on majority constituents such as transition metals (Fe, Co) and rare earth elements (Gd, Eu, Dy). In a second section, we first analyze the hf data on magnetic impurities (Ni, Co, Mn) diluted in Fe based amorphous ferromagnets (Fe-P-B, Fe-P-C). The case of 59Co diluted or concentrated in amorphous Gd-Co alloys is analyzed with some detail. Finally, we review the data on transferred hf on simple metals (Au) and s-p elements (P, B) is various amorphous ferromagnets. For those three cases, the mean hf value is discussed in the light of hf data on both pure elements and compositionally related crystalline compounds. The hf distribution is analyzed in relation with the structure of these amorphous alloys (electronic structure, magnetic structures, atomic-scale or medium-range atomic order). (orig.)