Charge and Zener polaron order in Bi0.75Sr0.25MnO3
Charge and Zener polaron order in Bi0.75Sr0.25MnO3
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Bi0.75Sr0.25MnO3 中的电荷和齐纳极化子顺序
DOI：
10.1103/physrevb.68.134408
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发表时间：
2003
影响因子：
3.7
通讯作者：
A. Calleja
中科院分区：
文献类型：
--
作者：
C. Frontera;J. García;M. Aranda;M. Hervieu;C. Ritter;L. Mañosa;X. G. Capdevila;A. Calleja
我们通过电子衍射、同步加速器X射线和中子粉末衍射等手段表征了Bi0.75Sr0.25MnO3的RT结构。这些数据证明 a;b;A2a p 和 c;2a p 平均结构呈现出使 a 和 c 晶格参数加倍的调制。使用磁化、量热测量和中子粉末衍射研究了该化合物在室温以上的温度演变。这些数据表明，上层建筑在 575 K 以上消失，并发生结构转变。磁化率数据表明，伴随着冷却时上部结构的形成，有效顺磁矩有所增强，正如在其他 Bi-(Sr,Ca)MnO3 铋锰矿中也发现的那样。观察到的特征和细胞演化表明，这种组合物中出现了一种新型的电荷和极化子排序。
We have characterized the RT structure of Bi0.75Sr0.25MnO3 by means of electron diffraction, synchrotron x-ray, and neutron powder diffraction. These data evidence that a;b;A2a p and c;2a p average structure presents a modulation that doubles the a and c lattice parameters. The temperature evolution of this compound above RT has been investigated using magnetization, calorimetry measurements, and neutron powder diffraction. These data reveal that the superstructure disappears above ;575 K where a structural transition takes place. Susceptibility data show that, concomitant to the formation of the superstructure ~on cooling!, there is an enhancement of the effective paramagnetic moment as has also been found in other Bi-(Sr,Ca)MnO3 bismuth manganites. The observed features and cell evolution signals that a new type of charge and polaron ordering occurs at this composition.