Metasurfaces provide an ideal platform for optical sensing because they produce strong light-field confinement and enhancement over extended regions that allow us to identify deep-subwavelength layers of organic and inorganic molecules. However, the requirement of using external light sources involves bulky equipment that hinders point-of-care applications. Here we introduce a plasmonic sensor with an embedded source of light provided by quantum tunnel junctions. An optically resonant, doubly periodic nanowire metasurface serves as a top contact for the junction and provides extremely uniform emission over large areas, amplified by plasmonic nanoantenna modes that simultaneously enhance the spectral and refractive index sensitivity. As a proof of concept, we demonstrate spatially resolved refractometric sensing of nanometre-thick polymer and biomolecule coatings. Our results open exciting prospects based on a disruptive platform for integrated electro-optical biosensors.

Luminescent composites based on entirely non-toxic, environmentally friendly compounds are in high demand for a variety of applications in photonics and optoelectronics. Carbon dots are a recently developed kind of luminescent nanomaterial that is eco-friendly, biocompatible, easy-to-obtain, and inexpensive, with a stable and widely tunable emission. Herein, we introduce luminescent composites based on carbon dots of different chemical compositions and with different functional groups at the surface which were embedded in a nanoporous silicate glass. The structure and optical properties of these composites were comprehensively examined using electron microscopy, Fourier transform infrared transmission, UV-Vis absorption, and steady-state and time-resolved photoluminescence. It is shown that the silicate matrix efficiently preserved, and even enhanced the emission of different kinds of carbon dots tested. The photoluminescence quantum yield of the fabricated nanocomposite materials reached 35–40%, which is comparable to or even exceeds the values for carbon dots in solution.

Hyperbolic metamaterials are a family of nanophotonic architectures allowing for the unique control of photonic local density of states. Such a property makes metamaterials prospective to use them with light-emitting objects or to apply as meta-electrodes for optoelectronic devices, where the control of recombination properties plays a decisive role. On the other hand, layered quasi-2D halide perovskites (Ruddlesden–Popper phase) attract high attention due to their low cost, broadband spectral tunability, and outstanding optoelectronic properties. Here, we show how to accelerate photoluminescence with smart engineering of photonic density of states (i.e., via the Purcell effect) by depositing a perovskite film on a hyperbolic metamaterial. We experimentally confirm acceleration of radiative recombination by almost 3 times. This effect can be useful in light-emitting devices, where interplay between radiative and non-radiative channels of charge carrier recombination is crucial.

The integration of nanoparticles (NPs) into functional materials is a powerful tool for the smart engineering of their physical properties. If properly designed and optimized, NPs possess unique optical, electrical, quantum, and other effects that will improve the efficiency of optoelectronic devices. Here, we propose a novel approach for the enhancement of perovskite light-emitting diodes (PeLEDs) based on electronic band structure deformation by core-shell NPs forming a metal-oxide-semiconductor (MOS) structure with an Au core and SiO${}_2$ shell located in the perovskite layer. The presence of the MOS interface enables favorable charge distribution in the active layer through the formation of hole transporting channels. For the PeLED design, we consider integration of the core-shell NPs in the realistic numerical model. Using our verified model, we show that, compared with the bare structure, the incorporation of NPs increases the radiative recombination rate of PeLED by several orders of magnitude. It is intended that this study will open new perspectives for further efficiency enhancement of perovskite-based optoelectronic devices with NPs.