Generalized synthesis of hybrid metal-semiconductor nanostructures tunable from the visible to the infrared

Hybrid superstructures allow a convenient route to the development of materials with multiple functionalities (e.g., sensor, marker, conductor) out of monofunctional (e.g., excitonic, plasmonic) building blocks. This work describes a general synthetic route to the preparation of metal|dielectric|quantum dot hybrid superstructures that have excitonic and plasmonic resonances independently tunable from the ultraviolet to the mid-infrared spectral region. We demonstrate that structural tuning can be used to control intercomponent coupling leading to the emergence of unique optical properties. We illustrate this capability by demonstrating single- and multicolor emission from coupled systems, and a significant enhancement of two-photon absorption cross sections of quantum dots. Such properties in a robust yet dispersible particle can be useful in a number of applications including bioimaging and microscopy, and in optoelectronic devices, as well as serve as a platform for fundamental studies of metal-semiconductor interactions.