Magnetic correlations in YBaCo4O7 probed by single-crystal neutron scattering

Journal article

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".

Authors: Manuel, P; Chapon, L; Radaelli, P; Zheng, H; Mitchell, J

• Journal: Phys. Rev. Lett.
• Volume: 103
• Issue: 3
• Pages: 037202
• Publication date: 2009-04-23
• DOI: 10.1103/PhysRevLett.103.037202
• EISSN: 1079-7114
• ISSN: 0031-9007
• Keywords: cond-mat.mtrl-sci; cond-mat.str-el