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arXiv · 0803.0293

X-ray absorption and x-ray magnetic dichroism study on Ca3CoRhO6 and Ca3FeRhO6

T. Burnus·Z. Hu·Hua Wu·J. C. Cezar·S. Niitaka·H. Takagi·C. F. Chang·N. B. Brookes·H. -J. Lin·L. Y. Jang·A. Tanaka·K. S. Liang·C. T. Chen·L. H. Tjeng
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Abstract

Using x-ray absorption spectroscopy at the Rh-L_2,3, Co-L_2,3, and Fe-L_2,3 edges, we find a valence state of Co^2+/Rh^4+ in Ca3CoRhO6 and of Fe^3+/Rh^3+ in Ca3FeRhO6. X-ray magnetic circular dichroism spectroscopy at the Co-L_2,3 edge of Ca3CoRhO6 reveals a giant orbital moment of about 1.7mu_B, which can be attributed to the occupation of the minority-spin d_0d_2 orbital state of the high-spin Co^2+ (3d^7) ions in trigonal prismatic coordination. This active role of the spin-orbit coupling explains the strong magnetocrystalline anisotropy and Ising-like magnetism of Ca3CoRhO6.

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T. Burnus, Z. Hu, Hua Wu, J. C. Cezar, S. Niitaka, H. Takagi, C. F. Chang, N. B. Brookes, H. -J. Lin, L. Y. Jang, A. Tanaka, K. S. Liang, C. T. Chen, L. H. Tjeng. 2008-03-03. X-ray absorption and x-ray magnetic dichroism study on Ca3CoRhO6 and Ca3FeRhO6. https://doi.org/10.1103/physrevb.77.205111

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