Novel artificial molecules: Optoelectronic properties of two quantum dots coupled by a quantum wire

Current work explores the potential offered by composite quantum nanostructures made of two quantum dots coupled by a quantum wire, which yields a quantum dumbbell. Using k · p model, we investigate electronic and optical properties of pyramidal dumbbells varying interdot spacing. We obtain that, in contrast with standard dot molecules, hybridization process and resulting molecular-type properties persist for increasing interdot distance up to more than 10 nm. The structural coupling plays the role of a tunable solid-state bond, which suggests that quantum dumbbells can be regarded as a new kind of metamolecules.