Variational approach for phonon renormalization effects in photoexcited quantum wires and quantum wells

Abstract

We investigate the effects of screening on polaronic corrections to the effective band edge in photoexcited quasi-one-dimensional GaAs quantum wires and two-dimensional quantum wells. We develop a variational method to calculate the polaron energy of a two-component plasma (electrons and holes) coupled to LO-phonons. Screening effects are incorporated within a dynamical scheme. We find that the screening effects and finite well width considerably reduce the polaron energy as the plasma density increases. Many-body corrections beyond the random-phase approximation are also considered.