Dynamic properties of solitons in the Frenkel-Kontorova Model. Application to incommensurate CDW conductors

An impact of kink-type solitons on infrared lattice vibrations is studied for incommensurate Frenkel-Kontorova model. It is shown that the vibration of particles involved into the kink formation is very similar to that in a gap mode around the force constant defect. IR phonon mode intensity is found to possess a universal dependence on the system parameters and the kink concentration. It is argued that the giant IR peak observed in a number of incommensurate charge density wave conductors can be explained in terms of dynamic charge transfer stimulated by kinks.