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Two Step Restoration of SU(2) Symmetry in a Frustrated Ring-Exchange Magnet

A. Laeuchli·J. C. Domenge·C. Lhuillier·P. Sindzingre·M. Troyer
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Abstract

We demonstrate the existence of a spin-nematic, moment-free phase in a quantum four-spin ring exchange model on the square lattice. This unusual quantum state is created by the interplay of frustration and quantum fluctuations which lead to a partial restoration of SU(2) symmetry when going from a four-sublattice orthogonal biaxial Neel order to this exotic uniaxial magnet. A further increase of frustration drives a transition to a fully gapped SU(2) symmetric valence bond crystal.

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A. Laeuchli, J. C. Domenge, C. Lhuillier, P. Sindzingre, M. Troyer. 2005-09-23. Two Step Restoration of SU(2) Symmetry in a Frustrated Ring-Exchange Magnet. https://doi.org/10.1103/physrevlett.95.137206

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