论文标题
Fe-ni Invar合金中的混合基态
Mixed ground state in Fe-Ni Invar alloys
论文作者
论文摘要
我们通过详细研究Fe $ _ {1-x} $ ni $ _x $合金（$ x $ = 0.2、0.4、0.4、0.5、0.6、0.7、0.9），使用$ x $ x $ -Ray ray potolectronspecopopy（xps），我们研究了invar合金的基态特性。虽然所有合金表现出柔软的铁磁行为，而居里温度却高于室温，但infar合金的结果是，fe $ _ {0.6} $ ni $ _ {0.4} $表现出异常行为。此外，在最终成员具有积极的磁力耐药性的同时，infar合金的磁性耐药性变为负面。 Invar合金的核心水平光谱表现出低于20〜K的新特征的出现，而所有其他FE-NI合金都没有温度依赖性降低至10〜K。有趣的是，与深度核心水平（2 $ s $，2 $ p $）相比，浅层核心水平光谱（3 $ s $，3 $ p $）在低温下显示出更强的偏差，表明水晶场效应。看来，在$α$相位的Fe中，抗铁磁$γ^\ prime $相位在20 K以下具有低磁矩（0.5 $μ_b$）的降水量。在低温下发现负磁耐药性，低温下的异常磁化以及在低温下核心水平上异常的新特征的出现提供了证据，证明了在Invar合金基底状态下混合相。
We investigate the ground state properties of Invar alloys via detailed study of the electronic structure of Fe$_{1-x}$Ni$_x$ alloys ($x$ = 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.9) employing $x$-ray photoelectron spectroscopy (XPS). While all the alloys exhibit soft ferromagnetic behavior with Curie temperature much higher than the room temperature, the results for invar alloy, Fe$_{0.6}$Ni$_{0.4}$ exhibit anomalous behavior. Moreover, the magneto-resistance of the Invar alloy becomes highly negative while the end members possess positive magneto-resistance. The core level spectra of the Invar alloy exhibit emergence of a distinct new feature below 20~K while all other Fe-Ni alloys exhibit no temperature dependence down to 10~K. Interestingly, the shallow core level spectra (3$s$, 3$p$) of Fe and Ni of the Invar alloy reveal stronger deviation at low temperatures compared to the deep core levels (2$s$, 2$p$) indicating crystal field effect. It appears that there is a large precipitation of antiferromagnetic $γ^\prime$ phase below 20 K possessing low magnetic moment (0.5$μ_B$) on Fe within the $α$ phase. The discovery of negative magneto-resistance, anomalous magnetization at low temperature and the emergence of unusual new features in the core levels at low temperature provide an evidence of mixed phase in the ground state of Invar alloys.
