Electron tunneling through thin barrier with smooth potential at GaAs/AlAs(001) heterointerfaces

The influence of actual microscopic potential on the characteristics of resonant electron tunneling from the Gamma valley in GaAs through the AlAs barrier with thickness of one lattice constant has been investigated by the methods of pseudopotential and scattering matrix factorized by the irreducible representations of the symmetry group of the heterostructure. The transition regions between the potentials of components and the barrier region are treated as the components of the Ga2Al2As4 superlattice spacing to provide the continuity of the crystal potential at the boundaries of the matching of wave functions. It is demonstrated that, compared to the results obtained in the abrupt-interface model, the inclusion of the actual potential in the calculation leads to changes in the number and location of the Fano resonances, an enhancement in the localization of electron density within the barrier, and a drastic increase in the tunneling time. (C) 2000 MAIK "Nauka/Interperiodica".