ELECTRONIC-STRUCTURE OF RARE-EARTH ARSENIDE GALLIUM-ARSENIDE SUPERLATTICES

We present linear-muffin-tin-orbital calculations of the energy band s tructure and of the density of states of semimetal-conductor superlatt ices made of rare earth arsenide (ErAs and YbAs) and GaAs. The effect of size quantization and the possibility of a semimetal-semiconductor transition is studied by varying the number of rare earth arsenide mon olayers buried in GaAs. We find that indeed a gap opens up in the band structure for the case of a single monolayer of YbAs embedded in GaAs , albeit well above the Fermi energy. The chances to induce a transiti on to a semiconductor are discussed. Copyright (C) 1996 Elsevier Scien ce Ltd