arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1201.3465cond-mat.mtrl-sci
收藏

α- Cr3(PO4)2的弱亚铁磁性和多重磁化反转

Weak ferrimagnetism and multiple magnetization reversal in α-Cr3(PO4)2

A. N. Vasiliev, O. S. Volkova, E. Hammer, R. Glaum, J. -M. Broto, M. Millot, G. Nénert, Y. T. Liu, J. -Y. Lin, R. Klingeler, M. Abdel-Hafiez, Y. Krupskaya, A. U… 展开作者

A. N. Vasiliev, O. S. Volkova, E. Hammer, R. Glaum, J. -M. Broto, M. Millot, G. Nénert, Y. T. Liu, J. -Y. Lin, R. Klingeler, M. Abdel-Hafiez, Y. Krupskaya, A. U. B. Wolter, B. Büchner

摘要:

正磷酸铬(II)α-Cr 3(PO 4)2是一种弱铁磁体,其居里温度TC = 29 K,比热为λ型峰。该系统中的主要反铁磁相互作用的特征是外斯温度Θ =-96 K,表明具有中等的阻挫比|Θ|/TC ~ 3.在其磁有序状态下,α-Cr 3(PO 4)2表现出对测量协议敏感的显著的温度诱导磁化反转序列,即场冷却或零场冷却制度。有效磁矩4.5 μB/Cr ~(2+)与纯自旋磁矩4.9 μB/Cr ~(2+)相比的减小不能归因于在Jahn-Teller活性3d ~ 4 Cr ~(2+)离子的任何晶体学位置中出现低自旋态。在K边的X射线吸收光谱表明二价铬,并解开这些离子在L2,3边的高自旋态。在该化合物中观察到的弱亚铁磁性和多次磁化反转现象可归因于Cr 2+在其六个晶体学上不等价位置的部分自发磁化函数的不完全抵消和扭曲。

英文摘要:

The chromium(II) orthophosphate α-Cr3(PO4)2 is a weak ferrimagnet with the Curie temperature TC = 29 K confirmed by a λ-type peak in specific heat. Dominant antiferromagnetic interactions in this system are characterized by the Weiss temperature Θ = - 96 K, indicating an intermediate frustration ratio |Θ|/TC ~ 3. In its magnetically ordered states α-Cr3(PO4)2 exhibits a remarkable sequence of temperature-induced magnetization reversals sensitive to the protocol of measurements, i.e. either field-cooled or zero-field-cooled regimes. The reduction of the effective magnetic moment 4.5 μB/Cr2+, as compared to the spin-only moment 4.9 μB/Cr2+, cannot be ascribed to the occurence of the low-spin state in any crystallographic site of the Jahn-Teller active 3d4 Cr2+ ions. X-ray absorption spectra at the K-edge indicate divalent chromium and unravel the high-spin state of these ions at the L2,3-edges. Weak ferrimagnetism and multiple magnetization reversal phenomena seen in this compound could be ascribed to incomplete cancellation and distortion of partial spontaneous magnetization functions of Cr2+ in its six crystallographically inequivalent positions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑