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arXiv · 1903.07887

Competition between intermediate plaquette phases in SrCu$_2$(BO$_3$)$_2$ under pressure

C. Boos·S. P. G. Crone·I. A. Niesen·P. Corboz·K. P. Schmidt·F. Mila
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Abstract

Building on the growing evidence based on NMR, magnetization, neutron scattering, ESR, and specific heat that, under pressure, SrCu$_2$(BO$_3$)$_2$ has an intermediate phase between the dimer and the Néel phase, we study the competition between two candidate phases in the context of a minimal model that includes two types of intra- and inter-dimer interactions without enlarging the unit cell. We show that the empty plaquette phase of the Shastry-Sutherland model is quickly replaced by a quasi-1D full plaquette phase when intra- and/or inter-dimer couplings take different values, and that this full plaquette phase is in much better agreement with available experimental data than the empty plaquette one.

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C. Boos, S. P. G. Crone, I. A. Niesen, P. Corboz, K. P. Schmidt, F. Mila. 2019-06-18. Competition between intermediate plaquette phases in SrCu$_2$(BO$_3$)$_2$ under pressure. https://doi.org/10.1103/physrevb.100.140413

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