Dependence of Electron g-Factor on Barrier Aluminum Content in GaAs/AlGaAs Quantum Wells

Abstract

The effects of quantum confinement on electron g-factor tensor components, g⊥ and g|| , were investigated for a wide variety of GaAs/AlxGa1-xAs quantum well structures, including the weak confinement regime, to determine the mapping of the g-factor components as functions of the aluminum content of an AlxGa1-xAs barrier and GaAs well thickness. The g-factor components were determined from the periods of electron spin precession, which were assessed by polarization- and time-resolved photoluminescence measurements under a magnetic field. The measured transverse component g⊥ was found to depend substantially on the barrier aluminum content, while the longitudinal component g|| was insensitive to the aluminum content. In addition to the experiments, the electron g-factor was analyzed theoretically on the basis of the three-band k·p perturbation theory by using Kiselev's method. Comparison of the experimental and theoretical results demonstrates that the three-band k·p calculation is sufficient to reproduce the main features of the experimental results including the effects of the barrier aluminum content.