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Investigation of soliton bound states in the Raman spectrum of pure and doped spin-Peierls chains

D. Augier·E. Sorensen·J. Riera·D. Poilblanc
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Abstract

We investigate the occurrence of singlet bound states in the Raman spectrum of dimerized spin 1/2 chains by Exact Diagonalization and Density Matrix Renormalization Group techniques. We predict that several bulk $δ$-peaks could be observed in pure systems. Furthermore, we show that new low energy lines arise from non-magnetic impurity doping. These features are interpreted in terms of soliton-antisoliton and soliton-impurity bound states respectively. Energies and spectral weights associated with these bound states are sensitive to lattice relaxation effects. Our results are discussed in the context of the inorganic spin-Peierls compound CuGeO$_3$ and quantitatively compared to recent Raman experiments.

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D. Augier, E. Sorensen, J. Riera, D. Poilblanc. 1999-08-03. Investigation of soliton bound states in the Raman spectrum of pure and doped spin-Peierls chains. https://doi.org/10.1103/physrevb.60.1075

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