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Weak ferromagnetism and field-induced spin reorientation in K2V3O8

M. D. Lumsden·B. C. Sales·D. Mandrus·S. E. Nagler·J. R. Thompson
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Abstract

Magnetization and neutron diffraction measurements indicate long-range antiferromagnetic ordering below TN=4 K in the 2D, S=1/2 Heisenberg antiferromagnet K2V3O8. The ordered state exhibits ``weak ferromagnetism'' and novel, field-induced spin reorientations. These experimental observations are well described by a classical, two-spin Heisenberg model incorporating Dzyaloshinskii-Moriya interactions and an additional c-axis anisotropy. This additional anisotropy can be accounted for by inclusion of the symmetric anisotropy term recently described by Kaplan, Shekhtman, Entin-Wohlman, and Aharony. This suggests that K2V3O8 may be a very unique system where the qualitative behavior relies on the presence of this symmetric anisotropy.

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M. D. Lumsden, B. C. Sales, D. Mandrus, S. E. Nagler, J. R. Thompson. 2000-08-23. Weak ferromagnetism and field-induced spin reorientation in K2V3O8. https://doi.org/10.1103/physrevlett.86.159

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