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Electron-lattice coupling, orbital stability and the phase diagram of Ca$_{2-x}$Sr$_x$RuO$_4$

Satoshi Okamoto·Andrew J. Millis
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Abstract

Hartree-Fock calculations are presented of a theoretical model describing the Sr/CaRuO$_4$ family of compounds. Both commensurate and incommensurate magnetic states are considered, along with orbital ordering and the effect of lattice distortions. For reasonable parameter values, interactions disfavor orbital disproportionation. A coherent description of the observed phase diagram is obtained.

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Satoshi Okamoto, Andrew J. Millis. 2004-04-05. Electron-lattice coupling, orbital stability and the phase diagram of Ca$_{2-x}$Sr$_x$RuO$_4$. https://doi.org/10.1103/physrevb.70.195120

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