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

Development of ANN Based Improved Model of Amplitude Response in Suppression State of Axonal Memory

659-663In this paper, three single-layered functional link artificial neural networks (FLANNs) based adaptive models are developed for generating improved responses for three high-frequency stimulations (HFS). It is in general observed that all the proposed FLANN models generate axonal responses which are in good agreement with the corresponding responses obtained from experiments. Further, it is demonstrated from simulation results that the responses obtained by the proposed model match better than that obtained by the theoretical model reported in the literature. Out of three FLANN models developed, the trigonometric FLANN model of suppression state of axonal memory is the best as it offers lowest of MAPE and MSE compared to those obtained by other two ANN models proposed in the paper