Optimized minigaps for negative differential resistance creation in strongly delta-doped (1D) superlattices

The 'atomic saw method' uses the passage of dislocations in two-dimensional (2D) quantum-well superlattices to create periodic slipping layers and one -dimensional (1D) quantum wire superlattices. The effects of this space str ucturing of the samples on the allowed energies are analysed in the case of GaAs delta-doped superlattices. If they are sufficiently large, the variou s minigaps appearing in the 1D band structure could be responsible for the presence of negative differential resistance (NDR) with high critical curre nt in these systems. The purpose is to determine the evolution of the minig aps in terms of the sample parameters and to obtain the means to determine both the 2D and 1D structural characteristics where NDR could appear. (C) 1 999 Academic Press.