Stark shift and field induced tunneling in doped quantum wells with arbitrary potential profiles

The energies and resonance widths of single doped quantum wells consisting of AlGaAs/GaAs with rectangular and annealing induced diffusion modified shapes are calculated under an uniform electric field using the stabilization method. The electronic structure is calculated without an electric field in the finite temperature density functional theory with exchange-correlation potential treated in the local density approximation. Our scheme for solving the Schrodinger and Poisson equations is based on the Fourier series method. The electric field is added to the self-consistent potential and energies are obtained as a function of the combined width of the well and barriers. This yields us the stabilization graph from which the energies and resonance widths at different field strengths are extracted using the Fermi Golden rule.published_or_final_versio

Electric field effect on the diffusion modified AlGaAs/GaAs single quantum well

The electron subband energies and wave functions in an interdiffusion-induced Al xGa 1-xAs/GaAs/Al xGa 1-xAs single quantum well are calculated in the presence of the dc electric field using the finite difference method. The mean lifetimes are obtained from the time-dependent probability of tunneling of the wave packet out of the well by the applied electric field. The effect of the applied electric field on the subband energies in the well is the same as in the as-grown square quantum well when the interdiffusion length is below 20 Å. In the well with higher diffusion length the barrier height reduces so that the wave function tunnels out of the well. The linear and nonlinear intersubband absorption coefficients and the change in the real part of the index of refraction are calculated with the applied electric field at 100 kV/cm and without the field in both the as-grown square well and the diffusion modified well with the interdiffusion length at 20 Å. © 1996 American Institute of Physics.published_or_final_versio