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arXiv · 1104.1461

Integer spin-chain antiferromagnetism of the 4d oxide CaRuO3 with post-perovskite structure

Y. Shirako·H. Satsukawa·X. X. Wang·J. J. Li·Y. F. Guo·M. Arai·K. Yamaura·M. Yoshida·H. Kojitani·T. Katsumata·Y. Inaguma·K. Hiraki·T. Takahashi·M. Akaogi
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Abstract

A quasi-one dimensional magnetism was discovered in the post-perovskite CaRuO3 (Ru4+: 4d4, Cmcm), which is iso-compositional with the perovskite CaRuO3 (Pbnm). An antiferromagnetic spin-chain function with -J/kB = 350 K well reproduces the experimental curve of the magnetic susceptibility vs. temperature, suggesting long-range antiferromagnetic correlations. The anisotropic magnetism is probably owing to the dyz - 2p- dzx and dzx - 2p- dyz superexchange bonds along a-axis. The Sommerfeld coefficient of the specific heat is fairly small, 0.16(2) mJ mol-1 K-2, indicating that the magnetism reflects localized nature of the 4d electrons. As far as we know, this is the first observation of an integer (S = 1) spin-chain antiferromagnetism in the 4d electron system.

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Y. Shirako, H. Satsukawa, X. X. Wang, J. J. Li, Y. F. Guo, M. Arai, K. Yamaura, M. Yoshida, H. Kojitani, T. Katsumata, Y. Inaguma, K. Hiraki, T. Takahashi, M. Akaogi. 2011-04-07. Integer spin-chain antiferromagnetism of the 4d oxide CaRuO3 with post-perovskite structure. https://doi.org/10.1103/physrevb.83.174411

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