Effects of lattice vibration on the properties of the strong-coupling polaron in a quantum well

In this paper, the effects of lattice vibration on the proper-ties of the polaron, which is weakly coupled with bulk longitudinal optical (LO) phonons and strongly coupled with interface optical (IO) phonons, in an infinite quantum well are studied by means of Huybrechts' linear-combination operator and the modified Lee-Low-Pines (LLP) variational method. The expressions for the self-trapping energy of the polaron in a quantum well as a function of the well width and temperature were derived. In particular, the law governing the change of the vibration frequency of the polaron with changing well width and temperature is obtained for the first time. Numerical results of the polaron self-trapping energy and the vibration frequency for KI/AgCl/KI QW show that the vibration frequency and the self-trapping energy of the polaron decrease with increasing well width and temperature, but the contributions of the interaction between the electron and the different branches of phonons to the self-trapping energy, the vibration frequency and the change of their variation with well width and temperature differ markedly.