Evidence of Spontaneous Co Moment in a Rare-Earth–Cobalt Laves Phase Compound:<sup>59</sup>Co NMR Study of LaCo<sub>2</sub>
作者:Hiroyuki Nakamura、Akihito Nakahara、Masayuki Shiga、A. V. Tsvyashchenko、L. N. Fomicheva
DOI:10.1143/jpsj.71.2117
日期:2002.9.15
cubic Lavesphasecompound LaCo 2 was investigated by 59 Co NMR experiments. At low temperatures, we found two kinds of NMR signals corresponding to small internal fields, -2.8 and 0.1 T, which are separated due to the anisotropy in the hyperfine field. This result reveals the weak ferromagnetism in LaCo 2 , indicating that a small spontaneous Co moment can exist in rare-earth–cobalt Lavesphase compounds
通过 59 Co NMR 实验研究了高压合成的立方 Laves 相化合物 LaCo 2 的基态磁性。在低温下,我们发现了两种对应于小内场的 NMR 信号,-2.8 和 0.1 T,由于超精细场的各向异性,它们被分开。该结果揭示了 LaCo 2 的弱铁磁性,表明在稀土-钴 Laves 相化合物中可以存在小的自发 Co 矩,既没有来自稀土原子的分子交换场,也没有无序的影响。有序矩和易磁化轴估计分别为 <0.1 µ B /Co 和 [111]。