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arXiv · 1506.02592

Spin nematics, valence-bond solids and spin liquids in SO($N$) quantum spin models on the triangular lattice

Ribhu K. Kaul
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Abstract

We introduce a simple model of SO($N$) spins with two-site interactions which is amenable to quantum Monte-Carlo studies without a sign problem on non-bipartite lattices. We present numerical results for this model on the two-dimensional triangular lattice where we find evidence for a spin nematic at small $N$, a valence-bond solid (VBS) at large $N$ and a quantum spin liquid at intermediate $N$. By the introduction of a sign-free four-site interaction we uncover a rich phase diagram with evidence for both first-order and exotic continuous phase transitions.

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Ribhu K. Kaul. 2015-06-08. Spin nematics, valence-bond solids and spin liquids in SO($N$) quantum spin models on the triangular lattice. https://doi.org/10.1103/physrevlett.115.157202

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