Prediction of orbital ordering in single-layered ruthenates.
Prediction of orbital ordering in single-layered ruthenates.
复制标题
DOI：
10.1103/physrevlett.88.017201
复制
发表时间：
2001-08
影响因子：
8.6
通讯作者：
T. Hotta;E. Dagotto
中科院分区：
文献类型：
--
作者：
T. Hotta;E. Dagotto
基于3-轨道Hubbard模型耦合到晶格畸变，使用数值和平均场技术，讨论了轨道自由度的关键作用，以了解层状磁致伸缩材料的磁性。在Ca（2）RuO（4）的G型反铁磁相中，最近的X射线实验报告在d（xy）轨道上有0.5个空穴/位，而d（yz）和d（zx）轨道上有1.5个空穴。这种意想不到的t（2g）空穴分布解释了一种新的轨道有序（OO）状态，稳定的库仑和晶格效应的组合。相图表明，大的磁电阻效应和一个新的铁磁OO相的可能性，在双烯酸盐。
The key role of the orbital degree of freedom to understanding the magnetic properties of layered ruthenates is discussed based on the 3-orbital Hubbard model coupled to lattice distortions, using numerical and mean-field techniques. In the G-type antiferromagnetic phase of Ca(2)RuO(4), recent x-ray experiments reported 0.5 holes/site in the d(xy) orbital, while d(yz) and d(zx) orbitals contain 1.5 holes. This unexpected t(2g) hole distribution is explained by a novel orbital ordered (OO) state, stabilized by a combination of Coulombic and lattice effects. The phase diagram suggests the possibility of large magnetoresistance effects and a new ferromagnetic OO phase in ruthenates.