Resonant coupling effects observed in independently contacted triple-quantum-well structures

Abstract

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