Polaron Zeeman effect in GaAs/AlxGa1−xAs multiple-quantum-well structures

Abstract

A three-level (1s, 2$p^{+}$, and 2$p^{\mathrm{-}}$ donor states) Wigner-Brillouin perturbation theory is used to study the resonant polaron Zeeman effect for an impurity placed at the center of a GaAs/${\mathrm{Al}}_{\mathrm{x}}$ ${\mathrm{Ga}}_{1\mathrm{-}\mathrm{x}}$As quantum-well structure in the presence of magnetic field. The resonant splitting caused by the polaron coupling between 1s and 2$p^{+}$ states and 2$p^{\mathrm{-}}$ and 2$p^{+}$ states as a function of well width is calculated. The results agree with experimental data if the GaAs LO-phonon energy is lowered to 250 ${\mathrm{cm}}^{\mathrm{-}1}$, which is believed to be caused by the zone folding of LO phonons in multiple-quantum-well structures.