Conduction-electron localized-moment interaction in palladium-silicon base amorphous alloys containing transition metals

[摘要] The electrical and magnetic properties of amorphous alloysobtained by rapid quenching from the liquid state have been studied.The composition of these alloys corresponds to the general formulaM_xPd_80-xSi₂₀, in which M stands for a metal of the first transitionseries between chromium and nickel and x is its atomic concentration.The concentration ranges within which an amorphous structure could beobtained were: from 0 to 7 for Cr, Mn and Fe, from 0 to 11 for Coand from 0 to 15 for Ni. A well-defined minimum in the resistivity vstemperature curve was observed for all alloys except those containingnickel. The alloys for which a resistivity minimum was observed had anegative magnetoresistivity approximately proportional to the squareof the magnetization and their susceptibility obeyed the Curie-Weisslaw in a wide temperature range. For concentrated Fe and Co alloysthe resistivity minimum was found to coexist with ferromagnetism.These observations lead to the conclusion that the present resultsare due to a s-d exchange interaction. The unusually high resistivityminimum temperature observed in the Cr alloys is interpreted as aresult of a high Kondo temperature and a large s-d exchange integral.A low Fermi energy of the amorphous alloys (3.5 eV) is also responsiblefor the anomalies due to the s-d exchange interaction.

[发布机构] University:California Institute of Technology;Department:Engineering and Applied Science

[关键词] Materials Science