RESONANT COUPLING EFFECTS OBSERVED IN INDEPENDENTLY CONTACTED TRIPLE-QUANTUM-WELL STRUCTURES

Independent contacts have been produced to all three two-dimensional e lectron gases (2DEGs) in a triple-quantum-well structure. This has bee n achieved by using in situ focused ion beam implantation followed by molecular beam epitaxial regrowth. Lateral transport studies of the in dividual layers have demonstrated resonant coupling between the high-m obility 2DEGs. Large resistance changes are observed due to coupling b etween the layers and these can be enhanced by having all three 2DEGs on resonance. A versatile device can thus be fabricated for studying e lectron interactions.