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arXiv · 0707.1195

Spontaneous trimerization in a bilinear-biquadratic S=1 zig-zag chain

Philippe Corboz·Andreas M. Laeuchli·Keisuke Totsuka·Hirokazu Tsunetsugu
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Abstract

Recent theoretical studies raised the possibility of a realization of spin nematic states in the S=1 triangular lattice compound NiGa_2S_4. We study the bilinear-biquadratic spin 1 chain in a zig-zag geometry by means of the density matrix renormalization group method and exact diagonalization. We present the phase diagram focusing on antiferromagnetic interactions. Adjacent to the known Haldane-double Haldane and the extended critical phase with dominant spin nematic correlations we find a trimerized phase with a nonvanishing energy gap. We discuss results for different order parameters, energy gaps, correlation functions, and the central charge, and make connection to field theoretical predictions for the phase diagram.

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Philippe Corboz, Andreas M. Laeuchli, Keisuke Totsuka, Hirokazu Tsunetsugu. 2008-01-21. Spontaneous trimerization in a bilinear-biquadratic S=1 zig-zag chain. https://doi.org/10.1103/physrevb.76.220404

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