非晶态NdxT1-x(T=Fe,Co,Ni)薄膜的低温磁性

本文讨论了非晶态Nd_xT_1-x(T=Fe,Co,Ni)薄膜为滋结构,以及在低温下磁化强度随温度变化的反常特性,在20K附近观测到磁化强度有陡降现象,并且在较大的成份范围内所对应的温度基本不变,我们认为,在这类非晶态合金中,当Nd含量超过一定值后,其磁中性态(通称基态)可能同时是散反铁磁性和散铁磁性的共存态,在20K附近的磁化强度发生陡降,是散反铁磁性←→顺磁性相转变的反映,这两种磁结构共存的临界成份相应约为:Nd-Fe情况x≥0.45;Nd-Co,x≥0.20;Nd-Ni,x≥0.08。 关键词：

LOW TEMPERATURE MAGNETIC PROPERTIES OF AMORPHOUS Ndx T1-x (T=Fe, Co, Ni) THIN FILMS

The magnetic structure and anomalous behavior of the temperature dependence of magnetization at low temperatures for amorphous Nd_xT_1-x(T=Fe, Co, Ni) thin films are discussed. It has been observed that the sudden drop of magnetization is at about 20 K, and the temperature corresponding to the sudden drop on the magnetization curves does not change with composition, we suggested that as the neodymium component exceeded a certain amount, in the ground state the asperomagnetic and the speromagnetie structures may coexist for these amorphous alloys. The sudden drop of magnetization at about 20K may be explained by the phase transition between the speromagne-tism and paramagnetism. The critical composition of neodymium component for eoexi-stance of these magnetic structures approximately corresponds to x≥0.45, 0.20 and 0.08 for Nd-Fe, Nd-Co and Nd-Ni amorphous thin films, respectively.