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Instability of isolated triplet excitations on the Shastry-Sutherland lattice (SSL)

A. Fledderjohann·K. -H. Muetter
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Abstract

Configurations of singlets and triplets on the SSL have been proposed in the literature as variational ground states of the Shastry-Sutherland model at fixed magnetization M. We prove, that isolated triplet excitations on the SSL are unstable if the coupling alpha falls below a critical value alpha_c=2.0 (approx.). The instability should be visible in the compound SrCu_2(BO_3)_2 where a coupling alpha^*=1.48 is realized.

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A. Fledderjohann, K. -H. Muetter. 2002-04-22. Instability of isolated triplet excitations on the Shastry-Sutherland lattice (SSL). https://doi.org/10.1103/physrevb.65.212406

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