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arXiv · 1211.1735

Stability of three-sublattice order in S=1 bilinear-biquadratic Heisenberg Model on anisotropic triangular lattices

Yu-Wen Lee·Yung-Chung Chen·Min-Fong Yang
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Abstract

The S=1 bilinear-biquadratic Heisenberg model on anisotropic triangular lattices is investigated by several complementary methods. Our focus is on the stability of the three-sublattice spin nematic state against spatial anisotropy. We find that, deviated from the case of isotropic triangular lattice, quantum fluctuations enhance and the three-sublattice spin nematic order is reduced. In the limit of weakly coupling chains, by mapping the systems to an effective one-dimensional model, we show that the three-sublattice spin nematic order develops at infinitesimal interchain coupling. Our results provide a complete picture for smooth crossover from the triangular-lattice case to both the square-lattice and the one-dimensional limits.

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Yu-Wen Lee, Yung-Chung Chen, Min-Fong Yang. 2012-11-08. Stability of three-sublattice order in S=1 bilinear-biquadratic Heisenberg Model on anisotropic triangular lattices. https://doi.org/10.7566/jpsj.82.034705

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