Interaction phenomena between deep levels and minibands in semiconductor superlattices.

It is shown that the introduction of deep levels in the barriers of tight-binding superlattices can have profound effects on the electronic states. By appropriate choice of the quantum well thickness and of the location of the deep center within the barrier strong mixing between the defect and superlattice states takes place. Enhancement of the miniband widths by several orders of magnitude and the creation of new Bloch states within the band-gap of the superlattice are found. Possible implementations of these new structures by Molecular Beam Epitaxy are discussed.