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Effective Theory of Magnetization Plateaux in the Shastry-Sutherland Lattice

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 نشر من قبل Capponi Sylvain
 تاريخ النشر 2008
  مجال البحث فيزياء
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We use the non-perturbative Contractor-Renormalization method (CORE) in order to derive an effective model for triplet excitations on the Shastry-Sutherland lattice. For strong enough magnetic fields, various magnetization plateaux are observed, e.g. at 1/8, 1/4, 1/3 of the saturation, as found experimentally in a related compound. Moreover, other stable plateaux are found at 1/9, 1/6 or 2/9. We give a critical review of previous works and try to resolve some apparent inconsistencies between various theoretical approaches.



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