Raman Scattering Investigation of High Temperature Ferromagnetic Crystals
Raman Scattering Investigation of High Temperature Ferromagnetic Crystals
复制标题
高温铁磁晶体的拉曼散射研究
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
Y. Yamaguchi
中科院分区：
文献类型：
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作者：
M. Udagawa;S. Nagai;N. Ogita;F. Iga;R. Kaji;Kazuyuki Sumida;J. Akimitsu;S. Kunii;Kazuya Z. Suzuki;H. Onodera;Y. Yamaguchi
用拉曼散射研究了铁磁性的CaB 6和CaB 2c2的声子谱，在CaB 6中，我们观察到E g声子的双重谱，并通过b6的各向异性电荷分布来理解。在铁磁性方面，由于a1g和e1g的声子峰强度在铁磁性居里温度附近发生变化，ca66的磁矩归因于b6八面体。这些结果可以用电子凝聚模型来解释。在c2c2中，观察到两种声子模式，但由于激光对样品的破坏，没有测量到更高温度下的光谱。在这两种铁磁晶体中，Ca与B/C之间的离子相互作用都小于稀土离子与B/C之间的离子相互作用。这一结果可能对阐明铁磁相互作用具有重要意义。
Phonon spectra of ferromagnetic CaB 6 and CaB 2 C 2 have been investigated by Raman scattering, In CaB 6 , a doublet spectrum has been observed for E g phonon and is understood by an anisotropic charge distribution at B 6 . For ferromagnetism, the magnetic moment of CaB 6 is attributed to the B 6 octahedron, since the intensity of the phonon peaks of A 1 g and E g changes in the vicinity of ferromagnetic Curie temperature. These results of CaB 6 are explained by electron condensate model. In CaB 2 C 2 , two phonon modes have been observed, but the spectra at higher temperature were not measured due to sample damage by laser. For both ferromagnetic crystals, the ionic interaction between Ca and B/C is smaller than that between rare earth ion and B/C in the isomorphous crystals. This result might be important to clarify a ferromagnetic interaction.