The Optical Polaron in Quantum-Well-Type Systems

Abstract

The polaron problem in a quasi 1D cylindrical quantum wire with infinite boundary potential is investigated using the strong-coupling theory and the mixed-coupling approximation. It is observed that a decrease in the radius of wire produces a pseudo- strong coupling aspect to the problem in spite of weak values of (α). A modification to the mixed-coupling theory is proposed to interpolate between the strong- and the weak-coupling aspects of the problem for all the degrees of confinements. This modified mixed-coupling approach is applied to the problem in a spherically box- type and in a slab like confinements. The same approach is applied to study the ground-state energy of the polaron as a function of the effective dimensionality. It is shown that the problem transforms from the strong-coupling to the weak-coupling limits in a smooth way.