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arXiv · 1706.06598

Generalization of the Haldane conjecture to SU(3) chains

Miklós Lajkó·Kyle Wamer·Frédéric Mila·Ian Affleck
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Abstract

We apply field theory methods to $\mbox{SU}(3)$ chains in the symmetric representation, with $p$ boxes in the Young tableau, mapping them into a flag manifold non-linear $\sigma$-model with a topological angle $\theta =2\pi p/3$. Generalizing the Haldane conjecture, we argue that the models are gapped for $p=3m$ but gapless for $p=3m\pm 1$ (for integer $m$), corresponding to a massless phase of the $\sigma$-model at $\theta =\pm 2\pi /3$. We confirm this with Monte Carlo calculations on the $\sigma$-model.

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Miklós Lajkó, Kyle Wamer, Frédéric Mila, Ian Affleck. 2017-06-20. Generalization of the Haldane conjecture to SU(3) chains. https://doi.org/10.1016/j.nuclphysb.2017.09.015

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