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arXiv · 0904.3690

Magnetic correlations in YBaCo4O7 probed by single-crystal neutron scattering

P. Manuel·L. C. Chapon·P. G. Radaelli·H. Zheng·J. F. Mitchell
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Abstract

We have studied the frustrated system YBaCo4O7 generally described as an alternating stacking of Kagome and triangular layers of magnetic ions on a trigonal lattice, by single crystal neutron diffraction experiments above the Neel ordering transition. Experimental data reveals pronounced magnetic diffuse scattering, which is successfully modeled by direct Monte-Carlo simulations. Long-range magnetic correlations are found along the c-axis, due to the presence of corner-sharing bipyramids, creating quasi one-dimensional order at finite temperature. In contrast, in the Kagome layers ab-plane, the spin-spin correlation function -displaying a short-range 120 degrees configuration- decays rapidly as typically found in spin-liquids. YBaCo4O7 experimentally realizes a new class of two-dimensional frustrated systems where the strong out-of-plane coupling does not lift the in-plane degeneracy, but instead act as an external "field".

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P. Manuel, L. C. Chapon, P. G. Radaelli, H. Zheng, J. F. Mitchell. 2009-04-23. Magnetic correlations in YBaCo4O7 probed by single-crystal neutron scattering. https://doi.org/10.1103/physrevlett.103.037202

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