Magnetic order and dynamics in an orbitally degenerate ferromagnetic insulator.
Magnetic order and dynamics in an orbitally degenerate ferromagnetic insulator.
复制标题
轨道简并铁磁绝缘体中的磁序和动力学。
DOI：
10.1103/physrevlett.89.167202
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发表时间：
2002
影响因子：
8.6
通讯作者：
B. Keimer
中科院分区：
文献类型：
--
作者：
C. Ulrich;G. Khaliullin;S. Okamoto;M. Reehuis;A. Ivanov;H. He;Y. Taguchi;Y. Tokura;B. Keimer
中子散射被用来确定自旋结构和磁振子谱的Mott-Hubbard绝缘体YTiO 3。磁结构是复杂的，包括大量的G型和A型反铁磁成分，除了占主导地位的铁磁成分。另一方面，磁振子谱是无带隙的，几乎是各向同性的。我们发现，这些发现是不一致的轨道有序状态，迄今提出的YTiO 3和讨论的一般意义的理论描述的轨道简并系统中的交换相互作用。
Neutron scattering was used to determine the spin structure and the magnon spectrum of the Mott-Hubbard insulator YTiO3. The magnetic structure is complex, comprising substantial G-type and A-type antiferromagnetic components in addition to the predominant ferromagnetic component. The magnon spectrum, on the other hand, is gapless and nearly isotropic. We show that these findings are inconsistent with the orbitally ordered states thus far proposed for YTiO3 and discuss general implications for a theoretical description of exchange interactions in orbitally degenerate systems.