The Phase Diagram of the Shastry-Sutherland Antiferromagnet

Zheng Weihong; J. Oitmaa; C. J. Hamer

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The Phase Diagram of the Shastry-Sutherland Antiferromagnet

Zheng Weihong·J. Oitmaa·C. J. Hamer

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Abstract

The Shastry-Sutherland model, which provides a representation of the magnetic properties of SrCu$_2$(BO$_3$)$_2$, has been studied by series expansion methods at T=0. Our results support the existence of an intermediate phase between the Néel long-range ordered phase and the short-range dimer phase. They provide strong evidence against the existence of helical order in the intermediate phase, and and somewhat less strong evidence against a plaquette-singlet phase. The nature of the intermediate phase thus remains elusive. It appears to be gapless, or nearly so.

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Zheng Weihong, J. Oitmaa, C. J. Hamer. 2001-07-02. The Phase Diagram of the Shastry-Sutherland Antiferromagnet. https://arxiv.org/abs/cond-mat/0107019

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