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arXiv · 1601.00793

Pressure dependence of the magnetization plateaus of SrCu_2(BO_3)_2

D. A. Schneider·K. Coester·F. Mila·K. P. Schmidt
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Abstract

We show that the critical fields of the magnetization plateaus of the Shastry-Sutherland model decrease significantly upon increasing the ratio of inter- to intra-dimer coupling, and accordingly that the magnetization plateaus of SrCu_2(BO_3)_2 shift to lower field under pressure, making the first two plateaus at 1/8 and 2/15 potentially accessible to neutron scattering experiments. These conclusions are based on the derivation of an effective classical model of interacting pinwheel-shaped spin-2 bound states using a combination of perturbative and graph-based continuous unitary transformations, showing that pinwheel crystals are indeed the lowest-energy plateau structures at low magnetization, and that a simple model of intermediate-range two-body repulsion between pinwheels is able to account quantitatively for the plateau sequence.

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D. A. Schneider, K. Coester, F. Mila, K. P. Schmidt. 2016-01-05. Pressure dependence of the magnetization plateaus of SrCu_2(BO_3)_2. https://doi.org/10.1103/physrevb.93.241107

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