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The Union Jack model: a quantum spin model with frustration on the square lattice

A. Collins·J. McEvoy·D. Robinson·C. J. Hamer·Zheng Weihong
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Abstract

A new quantum spin model with frustration, the `Union Jack' model on the square lattice, is analyzed using spin-wave theory. For small values of the frustrating coupling $α$, the system is N{\' e}el ordered as usual, while for large $α$ the frustration is found to induce a canted phase. The possibility of an intermediate spin-liquid phase is discussed.

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A. Collins, J. McEvoy, D. Robinson, C. J. Hamer, Zheng Weihong. 2005-11-18. The Union Jack model: a quantum spin model with frustration on the square lattice. https://arxiv.org/abs/cond-mat/0511451

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