The layered material SrCu2(BO3)2 has long been studied because of its fascinating physics in a magnetic field and under pressure. Many of its properties are remarkably well described by the Shastry-Sutherland model (SSM) - a two-dimensional frustrated spin system. However, the extent of the intermediate plaquette phase discovered in SrCu2(BO3)2 under pressure is significantly smaller than predicted in theory, which is likely due to the weak interlayer coupling that is present in the material but neglected in the model. Using state-of-the-art tensor network methods we study the SSM with a weak interlayer coupling and show that the intermediate plaquette phase is destabilized already at a smaller value around J′′/J∼0.04−0.05 than previously predicted from series expansion. Based on our phase diagram we estimate the effective interlayer coupling in SrCu2(BO3)2 to be around J′′/J∼0.027 at ambient pressure.
@article{arxiv.2302.07894,
title = {Tensor network study of the Shastry-Sutherland model with weak interlayer coupling},
author = {Patrick C. G. Vlaar and Philippe Corboz},
journal= {arXiv preprint arXiv:2302.07894},
year = {2023}
}