Unravelling the nonlinear generation of designer vortices with dielectric metasurfaces.

Vortex beams are currently drawing a great deal of interest, from fundamental research to several promising applications. While their generation in bulky optical devices limits their use in integrated complex systems, metasurfaces have recently proven successful in creating optical vortices, especially in the linear regime. In the nonlinear domain, of strategic importance for the future of classical and quantum information, to date orbital angular momentum has only been created in qualitative ways, without discussing discrepancies between design and experimental results.

Nonlinear spin-orbit coupling in optical thin films.

Tunable generation of vortex beams holds relevance in various fields, including communications and sensing. In this paper, we demonstrate the feasibility of nonlinear spin-orbit interactions in thin films of materials with second-order nonlinear susceptibility. Remarkably, the nonlinear tensor can mix the longitudinal and transverse components of the pump field.

Enhancement and tuning of the defect-induced electroluminescence of ZnO mesoporous layers in the visible range.

We show a way to pattern the visible electroluminescence of solution-processed mesoporous ZnO layers. Our approach consists in locally changing the nanoscale morphology of the coated ZnO layers by patterning the underlying surface with thin metallic patches. Above the metal, the ZnO film is organized in clusters that enhance its defect-induced electroluminescence.

Anomalous Absorption in Arrays of Metallic Nanoparticles: A Powerful Tool for Quantum Dot Optoelectronics.

Periodic arrays of noble metal nanoparticles are emblematic nanostructures in photonics. Their ability to sustain localized surface plasmon resonances has been used throughout the years to demonstrate a variety of passive and active functionalities such as enhanced luminescence in dipolar media and LEDs as well as higher responsivities in photoconductive detectors. Here, we show that additional magnetic resonances, associated with inductive current loops between the nanoparticles and accessible with transverse electric waves, emerge in the limit of dense arrays with subwavelength periods.

Bright CdSe/CdS Quantum Dot Light-Emitting Diodes with Modulated Carrier Dynamics via the Local Kirchhoff Law.

Addressing the interactions between optical antennas and ensembles of emitters is particularly challenging. Charge transfer and Coulomb interactions complicate the understanding of the carrier dynamics coupled by antennas. Here, we show how Au antennas enhance the luminescence of CdSe/CdS quantum dot assemblies through carrier dynamics control within the framework of the local Kirchhoff law.