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arXiv · 0805.4080

Quasi one-dimensional magnetism driven by unusual orbital ordering in CuSb2O6

Deepa Kasinathan·Klaus Koepernik·Helge Rosner
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Abstract

Essentially all undoped cuprates exhibit a quasi-planar, fourfold Cu-O coordination responsible for the magnetically active antibonding 3d-(x^2-y^2)-like state. Here, we present an electronic structure study for CuSb2O6 that reveals, in contrast, a half-filled 3d-(3z^2-r^2) orbital. This hitherto unobserved ground state originates from a competition of in- and out-of-plaquette orbitals where the strong Coulomb repulsion drives the surprising and unique orbital ordering. This, in turn, gives rise to an unexpected quasi one-dimensional magnetic behavior. Our results provide a consistent explanation of recent thermodynamical and neutron diffraction measurements.

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Deepa Kasinathan, Klaus Koepernik, Helge Rosner. 2008-05-27. Quasi one-dimensional magnetism driven by unusual orbital ordering in CuSb2O6. https://doi.org/10.1103/physrevlett.100.237202

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