Influence Of Pressure Effect On Binding Energies Of Impurity States In Quantum Wells With Finitely Thick Potential Barries

In this thesis, a variational method is adopted to investigate the binding energies of impurity states in GaAs/AlxGa1-xAs quantum wells with finitely thick potential barriers. The relations between binding energies of impurity states and well width, barrier thickness, impurity position, and Al concentration x are given by considering the influence of pressure effect and compared with that of quantum wells with infinitely thick barriers. Our results indicate that the binding energy for a quantum well with a finitely thick barrier is obviously less than that one with an infinitely thick barrier. Meanwhile, the difference of the binding energies of impurity states for the above cases is maximum when the well width is intermediate wide, whereas the difference is minimum for a wide well width. Moreover, the influence on the binding energy is also discussed by considering the variations of the electron effective mass, dielectric constant, and conduction band offset between the well and barriers with hydrostatic pressure. The conclusions are similar to that for quantum wells at zero pressure.