PROPAGATION OF QUASI-PARTICLES ON A DIMERIZED CHAIN

The problem of propagation for quasiparticles on a dimerized chain whi ch is modeled by alternating site energies and intersite interactions is investigated. Exact solutions for the propagators, the mean polariz ation and mean-square displacement are obtained, from which the role o f the site-energy mismatch and hopping disturbance on the behavior of the moving particle can be clearly seen. It is demonstrated that the i ncrease of the site-energy mismatch and the hopping disturbance will l ead to the enhancement of the localization.