Nd2Fe14B化合物磁晶各向异性起源的理论研究

本文根据Nd₂Fe₁₄B化合物中存有少量巡游电子的基本实验事实,提出了在Nd₂Fe₁₄B中配位子所产生的晶场和巡游电子所产生的电场共同造成了Nd离子磁晶各向异性的理论模型。提出并解决了计算巡游电子同中心Nd离子相互作用的理论方法。在同时考虑Nd离子所受配位子的晶场和巡游电子的电场的作用情况下,用单离子模型计算了Nd₂Fe₁₄B中Nd离子所产生的磁晶各向异性及其随温度的变化。所 关键词：

RESEARCH ON THE ORIGIN OF MAGNETO-CRYSTALLINE ANISOTROPY IN COMPOUND Nd2Fe14B

Based on the fact of the existance of a small amount itinerant electrons, a new theoretical model giving rise to magneto-crystalline anisotropy in compound Nd₂Fe₁₄B is presented in this paper. It is proposed that a combined effect on Nd-ion coming from both the crystal field of ligands and the electric field of itinerant electrons results in the anisotropy in the compound. An approach of calculating the interaction between itinerant electrons and central Nd-ion is given. The magneto-crystalline anisotropy of Nd-ion and its temperature dependences are calculated based on the model. The results are in good agreement with the experiments, and also give explanation to the spin reorientation phenomenon in the compound.