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arXiv · 0804.3974

Spin, Orbital and Charge Order at the Interface between Correlated Oxides

G. Jackeli·G. Khaliullin
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Abstract

The collective behavior of correlated electrons in the VO$_2-$interface layer of LaVO$_3$/SrTiO$_3$ heterostructure is studied within a quarter-filled $t_{2g}$-orbital Hubbard model on a square lattice. We argue that the ground state is ferromagnetic driven by the double exchange mechanism, and is orbitally and charge ordered due to a confined geometry and electron correlations. The orbital and charge density waves open gaps on the entire Fermi surfaces of all orbitals. The theory explains the observed insulating behavior of the $p$-type interface between LaVO$_3$ and SrTiO$_3$.

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G. Jackeli, G. Khaliullin. 2008-11-13. Spin, Orbital and Charge Order at the Interface between Correlated Oxides. https://doi.org/10.1103/physrevlett.101.216804

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