Kinks in One-Dimensional Electron-Phonon System with Commensurability 3 –Coupling Constant Dependence–

Abstract

Variations of fractionally charged kinks with coupling constant is investigated in the 1/3-filled Su-Schrieffer-Heeger model. Numerical analyses are carried out for chains consisting of about 480 lattice points. Creation energies and widths of kinks are calculated for various coupling constants. The weakest one yields a kink with a width of the order of 100 lattice constants. The electronic energy level structures have one or two localized gap states for kinks with charges ±2 e /3 or ± e /3, respectively. They remain to exist even in the case of the weakest coupling constant investigated.