Light–Matter Interactions between Germanium Nanocavities and Quantum Dots at Visible Wavelengths

Abstract

All-dielectric cavities are developed as a promising platform for light–matter interactions at visible wavelengths instead of plasmonic components because of their unique electromagnetic field confinement but lower losses. Here, thanks to the leaky magnetic resonance mode provided by germanium nanogrooves, a stronger light–matter interaction with cadmium selenide colloidal quantum dots has been experimentally demonstrated. The resulting Fano resonances exhibit that the asymmetric parameter q varies from 0.01 to 0.41 and the quality factor Q is up to 7.17 depending on the groove depth. Furthermore, the absorption of quantum dots and compact nanostructures near the groove mouth are found to be closely related to this coupling. Our findings present another available strategy to explore the coupling between resonant cavities and quantum emitters, which can promote the development of quantum optics and quantum information processing.

Collectively Enhanced Giant Circular Dichroism of Germanium Nanohelix Square Lattice Arrays

“…The emerging collective resonances strongly enhance and modify the chiroptical response of the array. It might also be considered that each individual helix within the lattice acts similar to a quantum‐dot‐like entity embedded in a resonant structure formed collectively by the crystal constituents [ 48 ] (surrounding helices).…”

Physical Chemistry of Quantum Information Science

“…Plasmonic nanostructures decorated with quantum dots have been explored as a platform to control their photoluminescence behavior, as in the work by H. Takase et al By optimizing the distance between the quantum dots, the photoluminescence intensity of a single quantum dot was enhanced due to plasmons. Y. Huang and G. Yang placed quantum dots in a resonant nanocavity to demonstrate enhanced light–matter interactions, which can promote the development of quantum optics and quantum information processing. A dielectric-metal hybrid materials system was proposed by F. Zhang et al to acquire optical nonlinearity enhancement, as compared to usually weak nonlinear optical responses in natural materials, via strong coupling with a localized surface plasmon in a nanocavity.…”