EFFECTS OF THE LATTICE DISCRETENESS ON A SOLITON IN THE SU-SCHRIEFFER-HEEGER MODEL

In this paper pre analytically study the effects of the lattice discre teness on the electron band in the SSH model. We propose a modified ve rsion of the TLM model which is derived from the SSH model using a con tinuum approximation. When a soliton is induced in the electron-lattic e system, the electron scattering states both at the bottom of the val ence band and the top of the conduction band are attracted to the soli ton. This attractive force induces weakly localized electronic states at the band edges. Using the modified version of the TLM model, we hav e succeeded in obtaining analytical solutions of the weakly localized states and the extended states near the bottom of the valence band and the top of the conduction band. This band structure does not modify t he order parameters. Our result coincides well with numerical simulati on works.