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arXiv · 0807.4489

The nature of the magnetic order in Ca3Co2O6

S. Agrestini·L. C. Chapon·A. Daoud-Aladine·J. Schefer·A. Gukasov·C. Mazzoli·M. R. Lees·O. A. Petrenko
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Abstract

We present a detailed powder and single crystal neutron diffraction study of the spin chain compound Ca3Co2O6. Below 25 K, the system orders magnetically with a modulated partially disordered antiferromagnetic structure. We give a description of the magnetic interactions in the system which is consistent with this magnetic structure. Our study also reveals that the long-range magnetic order co-exists with a shorter range order with a correlation length scale of 180 A in the ab plane. Remarkably, on cooling, the volume of material exhibiting short range order increases at the expense of the long-range order.

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S. Agrestini, L. C. Chapon, A. Daoud-Aladine, J. Schefer, A. Gukasov, C. Mazzoli, M. R. Lees, O. A. Petrenko. 2008-07-28. The nature of the magnetic order in Ca3Co2O6. https://doi.org/10.1103/physrevlett.101.097207

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