Quantum confined stark effect and optical absorption in Al_xGa_1−xAs/GaAs/Al_xGa_1−xAs

The effects of the electric field on the electron subband energies and wavefunctions in a single quantum well Al_xGa_1−xAs/GaAs/Al_xGa_1−x As have been calculated using an analytic method which takes into account the variation of the effective mass at the barriers. The results are compared with the previous calculations which took the effective mass of GaAs inside and outside the well. The calculated energies and wavefunctions together with the experimental linewidth broadening are used to obtain the inter-subband optical absorption spectra and the change in the real part of the index of refraction in the well.