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Magnetic Phase Diagram of Ca2-xSrxRuO4 Governed by Structural Distortions

Zhong Fang·Kiyoyuki Terakura
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Abstract

We constructed, by the first-principles calculations, a magnetic phase diagram of Sr$_{2}$RuO$_4$ in the space spanned by structural distortions. Our phase diagram can qualitatively explain the experimental one for Ca$_{2-x}$Sr$_x$RuO$_4$. We found that the rotation and the tilting of RuO$_6$ octahedron are responsible for the ferro- and antiferro-magnetism, respectively, while the flattening of RuO$_6$ is the key factor to stabilize those magnetic ground states. Our results imply that the magnetic and the structural instabilities in Sr$_2$RuO$_4$ are closely correlated cooperatively rather than competitively.

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Zhong Fang, Kiyoyuki Terakura. 2001-03-09. Magnetic Phase Diagram of Ca2-xSrxRuO4 Governed by Structural Distortions. https://doi.org/10.1103/physrevb.64.020509

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