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arXiv · 0808.1009

Incommensurate spin density modulation in a copper-oxide chain compound with commensurate charge order

M. Raichle·M. Reehuis·G. André·L. Capogna·M. Sofin·M. Jansen·B. Keimer
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Abstract

Neutron diffraction has been used to determine the magnetic structure of Na$_8$Cu$_5$O$_{10}$, a stoichiometric compound containing chains based on edge-sharing CuO$_4$ plaquettes. The chains are doped with 2/5 hole per Cu site and exhibit long-range commensurate charge order with an onset well above room temperature. Below $T_N = 23$ K, the neutron data indicate long-range collinear magnetic order with a spin density modulation whose propagation vector is commensurate along and incommensurate perpendicular to the chains. Competing interchain exchange interactions are discussed as a possible origin of the incommensurate magnetic order.

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M. Raichle, M. Reehuis, G. André, L. Capogna, M. Sofin, M. Jansen, B. Keimer. 2008-08-07. Incommensurate spin density modulation in a copper-oxide chain compound with commensurate charge order. https://doi.org/10.1103/physrevlett.101.047202

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