Ye Xubin, Zhao Jianfa, Das Hena, Sheptyakov Denis, Yang Junye, Sakai Yuki, Hojo Hajime, Liu Zhehong, Zhou Long, Cao Lipeng, Nishikubo Takumi, Wakazaki Shogo, Dong Cheng, Wang Xiao, Hu Zhiwei, Lin Hong-Ji, Chen Chien-Te, Sahle Christoph, Efiminko Anna, Cao Huibo, Calder Stuart, Mibu Ko, Kenzelmann Michel, Tjeng Liu Hao, Yu Runze, Azuma Masaki, Jin Changqing, Long Youwen
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, China.
School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2021 Mar 26;12(1):1917. doi: 10.1038/s41467-021-22064-9.
PbMO (M = 3d transition metals) family shows systematic variations in charge distribution and intriguing physical properties due to its delicate energy balance between Pb 6s and transition metal 3d orbitals. However, the detailed structure and physical properties of PbFeO remain unclear. Herein, we reveal that PbFeO crystallizes into an unusual 2a × 6a × 2a orthorhombic perovskite super unit cell with space group Cmcm. The distinctive crystal construction and valence distribution of PbPbFeO lead to a long range charge ordering of the -A-B-B- type of the layers with two different oxidation states of Pb (Pb and Pb) in them. A weak ferromagnetic transition with canted antiferromagnetic spins along the a-axis is found to occur at 600 K. In addition, decreasing the temperature causes a spin reorientation transition towards a collinear antiferromagnetic structure with spin moments along the b-axis near 418 K. Our theoretical investigations reveal that the peculiar charge ordering of Pb generates two Fe magnetic sublattices with competing anisotropic energies, giving rise to the spin reorientation at such a high critical temperature.
PbMO（M = 3d过渡金属）家族由于其Pb 6s和过渡金属3d轨道之间微妙的能量平衡，在电荷分布和有趣的物理性质方面呈现出系统的变化。然而，PbFeO的详细结构和物理性质仍不清楚。在此，我们揭示PbFeO结晶为具有空间群Cmcm的不寻常的2a×6a×2a正交钙钛矿超晶胞。PbPbFeO独特的晶体结构和价态分布导致层中具有两种不同氧化态的Pb（Pb和Pb）的-A-B-B-型长程电荷有序。发现沿着a轴具有倾斜反铁磁自旋的弱铁磁转变在600 K发生。此外，降低温度会导致在418 K附近向具有沿b轴自旋矩的共线反铁磁结构的自旋重取向转变。我们的理论研究表明，Pb的特殊电荷有序产生了两个具有竞争各向异性能量的Fe磁亚晶格，从而在如此高的临界温度下产生自旋重取向。
