Local spin ordering in the antiferromagnetic as well as paramagnetic LaMnO3 phase revealed by polarized spin-selected 1s→3d absorption spectra
Local spin ordering in the antiferromagnetic as well as paramagnetic LaMnO3 phase revealed by polarized spin-selected 1s→3d absorption spectra
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DOI：
10.1103/physrevb.73.134405
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发表时间：
2006-04-01
影响因子：
3.7
通讯作者：
Garg, KB
中科院分区：
文献类型：
--
作者：
Hayashi, H;Sato, A;Garg, KB
用极化x射线研究了45 K （a型反铁磁相）和273 K（顺磁相）单晶LaMnO3的自旋选择x射线吸收近边结构。观测到的极化特征被解释为Mn - 4p轨道与相邻Mn离子的三维轨道的杂化以及跃迁时的自旋不变性。在两种极化谱中几乎没有观察到温度依赖性，表明即使在远高于T-N的温度下也存在短程自旋顺序。通过假设x射线吸收过程如此快速，对中心吸收Mn离子附近的时间局部结构敏感，可以解决与体磁性的明显矛盾。
Spin-selected x-ray absorption near edge structures have been studied on single crystal LaMnO3 at 45 K (A-type antiferromagnetic phase) and at 273 K (paramagnetic phase) with polarized x rays. Observed polarization characters have been interpreted in terms of hybridization of Mn 4p orbitals with 3d orbitals of adjacent Mn ions combined with spin-invariance upon transitions. Almost no temperature dependence was observed in the spectra of both polarization, indicating that short-range spin order exists even at a temperature much higher than T-N. An apparent contradiction of the result with bulk magnetic properties can be resolved by assuming that the x-ray absorption process, being so fast, is sensitive to temporal local structures in the vicinity of the central absorbing Mn ion.