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Spin nematics in the bilinear-biquadratic S=1 spin chain

A. Laeuchli·G. Schmid·S. Trebst
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Abstract

We report the existence of an extended critical, nondimerized region in the phase diagram of the bilinear-biquadratic spin-one chain. The dominant power law correlations are ferroquadrupolar, i.e. spin nematic in character. Another known critical region is also characterized by dominant quadrupolar correlations, although with a different wave vector. Our results show that spin nematic correlations play an important role in quantum magnets with spin S >= 1 in regions between antiferromagnetic and ferromagnetic phases.

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A. Laeuchli, G. Schmid, S. Trebst. 2003-11-05. Spin nematics in the bilinear-biquadratic S=1 spin chain. https://doi.org/10.1103/physrevb.74.144426

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