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

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.

RevTex file, 3 ps figures

Cited by in corpus (2)

• Spin Dynamics of the One-Dimensional J-J' Model and Spin-Peierls Transition in CuGeO_3
• Dimer and Néel order-parameter fluctuations in the spin-fluid phase of the s=1/2 spin chain with first and second neighbor couplings