Electrodynamical enhancement of optical transitions in semiconductor and metal–semiconductor nanostructures

Semiconductor and metal–semiconductor nanostructures are shown to exhibit electrodynamical resonances analogous to the Fröhlich resonance for metal nanoparticles in a dielectric host. If the transition frequency of an optical transition in the nanostructure core coincides with one of the resonance frequencies of the nanostructure, the strength of the optical transition is dramatically enhanced by up to 4–6 orders of magnitude. The resonance frequencies are determined by dielectric permittivities of materials of host and nanostructure, and by sizes of the nanostructure. That enables to tune the resonance frequencies to desired values in an extremely wide spectral range—from ultraviolet to terahertz, engineering thus optical properties of high-efficiency nanostructured optical materials for numerous applications.