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Spin waves and the origin of commensurate magnetism in Ba2CoGe2O7

A. Zheludev·T. Sato·T. Masuda·K. Uchinokura·G. Shirane·B. Roessli
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Abstract

The square-lattice antiferromagnet Ba2CoGe2O7 is studied by means of neutron diffraction and inelastic scattering. This material is isostructural to the well-known Dzyaloshinskii-Moriya helimagnet Ba2CuGe2O7, but exhibits commensurate long-range Neel order at low temperatures. Measurements of the spin wave dispersion relation reveal strong in-plane anisotropy that is the likely reason for the suppression of helimagnetism.

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A. Zheludev, T. Sato, T. Masuda, K. Uchinokura, G. Shirane, B. Roessli. 2003-02-27. Spin waves and the origin of commensurate magnetism in Ba2CoGe2O7. https://doi.org/10.1103/physrevb.68.024428

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