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arXiv · 1402.0901

Cooperative effects of Jahn-Teller distortion, magnetism and Hund's coupling in the insulating phase of BaCrO$_3$

G. Giovannetti·M. Aichhorn·M. Capone
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Abstract

We employ a combination of density functional theory and dynamical mean-field theory to investigate the electronic structure of the recently synthesized insulator BaCrO$_3$. Our calculations show that Hund's coupling is responsible for strong correlation effects, which are however not sufficient to turn the system insulating. A finite Jahn-Teller distortion lifting the orbital degeneracy is necessary to stabilize an insulating state with orbital ordering and consequent magnetic ordering.

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G. Giovannetti, M. Aichhorn, M. Capone. 2014-02-04. Cooperative effects of Jahn-Teller distortion, magnetism and Hund's coupling in the insulating phase of BaCrO$_3$. https://doi.org/10.1103/physrevb.90.245134

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