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arXiv · 1009.4338

Local symmetry and magnetic anisotropy in multiferroic MnWO4 and antiferromagnetic CoWO4 studied by soft x-ray absorption spectroscopy

N. Hollmann·Z. Hu·T. Willers·L. Bohaty·P. Becker·A. Tanaka·H. H. Hsieh·H. -J. Lin·C. T. Chen·L. H. Tjeng
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Abstract

Soft x-ray absorption experiments on the transition metal L2,3 edge of multiferroic MnWO4 and antiferromagnetic CoWO4 are presented. The observed linear polarization dependence, analyzed by full-multiplet calculations, is used to determine the ground state wave function of the magnetic Mn2+ and Co2+ ions. The impact of the local structure and the spin-orbit coupling on the orbital moment is discussed in terms of the single-ion anisotropy. It is shown that the orbital moment in CoWO4 is responsible for the collinear antiferromagnetism, while the small size of spin-orbit coupling effects make spiral magnetic order in MnWO4 possible, enabling the material to be multiferroic.

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N. Hollmann, Z. Hu, T. Willers, L. Bohaty, P. Becker, A. Tanaka, H. H. Hsieh, H. -J. Lin, C. T. Chen, L. H. Tjeng. 2010-09-22. Local symmetry and magnetic anisotropy in multiferroic MnWO4 and antiferromagnetic CoWO4 studied by soft x-ray absorption spectroscopy. https://doi.org/10.1103/physrevb.82.184429

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