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arXiv · 0806.3406

Theory of magnetization plateaux in the Shastry-Sutherland model

J. Dorier·K. P. Schmidt·F. Mila
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Abstract

Using perturbative continuous unitary transformations, we determine the long-range interactions between triplets in the Shastry-Sutherland model, and we show that an unexpected structure develops at low magnetization with plateaux progressively appearing at 2/9, 1/6, 1/9 and 2/15 upon increasing the inter-dimer coupling. A critical comparison with previous approaches is included. Implications for the compound SrCu$_2$(BO$_3$)$_2$ are also discussed: we reproduce the magnetization profile around localized triplets revealed by NMR, we predict the presence of a 1/6 plateau, and we suggest that residual interactions beyond the Shastry-Sutherland model are responsible for the other plateaux below 1/3.

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J. Dorier, K. P. Schmidt, F. Mila. 2008-06-20. Theory of magnetization plateaux in the Shastry-Sutherland model. https://doi.org/10.1103/physrevlett.101.250402

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