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Dynamics of quantum spin systems in dimer and valence-bond solid ground states stabilized by competing interactions

Yongmin Yu·Gerhard Müller
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Abstract

For special coupling ratios, the one-dimensional (1D) s=1/2 Heisenberg model with antiferromagnetic nearest and next-nearest neighbor interactions has a pure dimer ground state, and the 1D s=1 Heisenberg model with antiferromagnetic bilinear and biquadratic interactions has an exact valence-bond-solid ground state. The recursion method is used to calculate the T=0 spin dynamic structure factor for both models and, for the s=1/2 model, also the dimer dynamic structure factor. New results for line shapes and dynamically relevant dispersions are obtained.

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Yongmin Yu, Gerhard Müller. 1995-08-25. Dynamics of quantum spin systems in dimer and valence-bond solid ground states stabilized by competing interactions. https://doi.org/10.1063/1.361686

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