Quantum corrections to solitons in polyacetylene

The quantum corrections on the soliton in polyacetylene is studied within the continuum version of the Su, Schrieffer, and Heeger model. First, the optical-phonon spectrum in the presence of a soliton is determined. It is shown that the soliton generates two localized phonon modes; the one with ω=0 corresponds to the translation of the soliton, while the other with ω0.8ω₀ is Raman active where ω₀ is the optical-phonon frequency with $k=0$. The quantum correction to the soliton energy Eₛ is also calculated. We find the correction is rather important: δEₛ-1/4Eₛ.