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Field-Induced Effects of Anisotropic Magnetic Interactions in SrCu2(BO3)2

K. Kodama·S. Miyahara·M. Takigawa·M. Horvatic·C. Berthier·F. Mila·H. Kageyama·Y. Ueda
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Abstract

We observed a field-induced staggered magnetization in the 2D frustrated dimer-singlet spin system SrCu2(BO3)2 by 11B NMR, from which the magnitudes of the intradimer Dzyaloshinsky-Moriya interaction and the staggered g-tensor were determined. These anisotropic interactions cause singlet-triplet mixing and eliminate a quantum phase transition at the expected critical field Hc for gap closing. They also provide a quantitative account for some puzzling phenomena such as the onset of a uniform magnetization below the and the persistence of the excitation gap above Hc. The gap was accurately determined from the activation energy of the nuclear relaxation rate.

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K. Kodama, S. Miyahara, M. Takigawa, M. Horvatic, C. Berthier, F. Mila, H. Kageyama, Y. Ueda. 2005-01-21. Field-Induced Effects of Anisotropic Magnetic Interactions in SrCu2(BO3)2. https://doi.org/10.1088/0953-8984%2F17%2F4%2Fl02

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