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Dynamical effects of phonons on soliton binding in spin-Peierls systems

D. Augier·D. Poilblanc·E. Sorensen·I. Affleck
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Abstract

The role of dynamical magneto-elastic coupling in spin-Peierls chains is investigated by numerical and analytical techniques. We show that a Heisenberg spin chain coupled to dynamical optical phonons exhibits a transition towards a spontaneously dimerized state in a wide range of parameter space. The low energy excitations are characterized as solitons. No binding between solitons occurs in the isolated spin-phonon chain and the dynamical spin structure factor shows a broad magnon dispersion. However, elastic interchain coupling can lead to the formation of bound states.

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D. Augier, D. Poilblanc, E. Sorensen, I. Affleck. 1998-03-11. Dynamical effects of phonons on soliton binding in spin-Peierls systems. https://doi.org/10.1103/physrevb.58.9110

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