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arXiv · 1212.2983

Tensor network study of the Shastry-Sutherland model in zero magnetic field

Philippe Corboz·Frederic Mila
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Abstract

We simulate the Shastry-Sutherland model in two dimensions by means of infinite projected entangled-pair states (iPEPS) - a variational tensor network method where the accuracy can be systematically controlled by the so-called bond dimension. Besides the well established dimer and N\'eel phase iPEPS confirms the presence of an intermediate phase with plaquette long-range order, and we determine its phase boundaries with high accuracy. The first order phase transition for $J=0.675(2)$ between dimer and plaquette phase is compatible with previous series expansion results. iPEPS predicts a weak first-order phase transition between plaquette and N\'eel phase occurring for $J=0.765(15)$. We do not find a stable intermediate columnar-dimer phase, even when we bias the state towards this order.

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Philippe Corboz, Frederic Mila. 2012-12-12. Tensor network study of the Shastry-Sutherland model in zero magnetic field. https://doi.org/10.1103/physrevb.87.115144

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