论文标题
在钙钛矿型铁氧化物（SR $ _ {1-x} $ ba $ _x $）$ _ {2/3} $ la $ _ {1/3} $ _3 $ _3 $ _3 $
Spin-charge coupling and decoupling in perovskite-type iron oxides (Sr$_{1-x}$Ba$_x$)$_{2/3}$La$_{1/3}$FeO$_3$
论文作者
论文摘要
已知钙蛋白型氧化铁Sr $ _ {2/3} $ la $ _ {1/3} $ feo $ _3 $众所周知可以显示特征性的自旋订购（SCO），其中六倍胶线旋转订购和三倍的费用订购与彼此相连。在这里，我们报告了旋转电荷解耦和抗铁磁性（AFM）状态的发现，与perovskites（sr $ _ {1-x} $ ba $ _x $ _X $）$ _ {2/3} $ la $ _ $ _ {1/3} $ _ {1/3} $ feo $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $ _3 $。通过包括中子衍射，M $ $ SSBAUER光谱和X射线吸收光谱在内的全面测量，我们发现Isovalent Ba $^{2+} $替代系统地降低了SCO相位的关键温度，此外还可以在$ x $ x 0.75 $ x $ x 0.75中产生旋转键盘分解。尽管基态在整个$ x $区域中仍处于SCO阶段，但意外的G型AFM阶段具有不一致的收费订购或费用波动，作为高温阶段$ x $> 0.75的高温阶段。反映它们之间的竞争性质，G型AFM阶段在低温下在SCO阶段中部分存在作为亚稳态。我们讨论了旋转电荷解耦的起源以及G型AFM相的出现，并从BA取代的带宽减少方面具有电荷波动。
The perovskite-type iron oxide Sr$_{2/3}$La$_{1/3}$FeO$_3$ is known to show characteristic spin-charge ordering (SCO), where sixfold collinear spin ordering and threefold charge ordering are coupled with each other. Here, we report the discovery of a spin-charge decoupling and an antiferromagnetic (AFM) state competing with the SCO phase in perovskites (Sr$_{1-x}$Ba$_x$)$_{2/3}$La$_{1/3}$FeO$_3$. By comprehensive measurements including neutron diffraction, M$ö$ssbauer spectroscopy, and x-ray absorption spectroscopy, we found that the isovalent Ba$^{2+}$ substitution systematically reduces the critical temperature of the SCO phase and additionally yields the spin-charge decoupling in $x$ > 0.75. Whereas the ground state remains in the SCO phase in the whole $x$ region, an unexpected G-type AFM phase with incoherent charge ordering or charge fluctuation appears as the high-temperature phase in the range of $x$ > 0.75. Reflecting the competing nature between them, the G-type AFM phase partially exists as a metastable state in the SCO phase at low temperatures. We discuss the origin of the spin-charge decoupling and the emergence of the G-type AFM phase with charge fluctuation in terms of the bandwidth reduction by the Ba substitution.
