A new generation of lenses - metalenses - is starting to replace bulky curved lenses with simple, flat surfaces that use nanostructures to focus light. These flat surfaces - meatsurfaces - have enabled the design of diffraction-based flat devices to replicate the functionalities of conventional lenses with sub-wavelength or few-wavelength thicknesses. Researchers have now successfully designed and experimentally demonstrated an inverse-designed metalens to operate at a near-infrared ...
Researchers have developed a high-throughput, scalable nanocomposite printing method to manufacture metalenses at low cost, paving the way to commercializing them. The nanocomposite material, which is also suitable for high-efficiency metasurfaces, can be molded into metalenses just by one step of printing without any secondary operations such as thin-film deposition or plasma etching. The researchers synthesized their nanocomposite by dispersing silicon nanoparticles in the matrix of ...
Inspired by chiral molecular structures, scientists are developing strategies to build artificial chiral materials by mimicking natural molecular structures using functional materials. Specifically, metal nanomaterials exhibit tailorable optical properties upon excitation of surface plasmons and become one of the most promising components to realize chiral optical metamaterials. Researchers now demonstrate all-solid-phase reconfigurable chiral nanostructures, where the geometry and ...
A major challenge for nanophotonics engineers is the wide range of optical responses that metamaterials and other nanoplasmonic structures can generate. In the past few years, machine learning has emerged as a powerful tool for sifting through this vast universe of possible design parameters to aid the design of nanophotonic devices tailored for specific applications. A novel approach uses a type of neural network called a mixture density network to solve the non-uniqueness problem of ...
Inspired by chiral molecular structures, scientists are developing strategies to build artificial chiral materials by mimicking natural molecular structures using functional materials. Specifically, metal nanomaterials exhibit tailorable optical properties upon excitation of surface plasmons and become one of the most promising components to realize chiral optical metamaterials. New work provides a macroscopic model to understand the origin of chirality because the structures of the ...
4D printing allows a 3D printed structure to change its configuration or function with time in response to external stimuli such as temperature, light, water, pH, etc. The basic idea is to manipulate materials at nano and micro levels in order to produce, via 3D printing, materials that can modify their structures over time at the macro level. Based on 4D printing, 3D printed objects from nano- to macroscale can be fabricated as smart devices, metamaterials, and origami for various ...
Over the past several years, metal nanoparticles photosensitization over semiconductors with a large band gap has emerged as a promising strategy for developing visible-light responsive photocatalytic materials. In new work, researchers demonstrate a new plasmonic metamaterial can absorb nearly 100% of incident light (of a specific color) and use this energy to accelerate the production of chemicals. In constructing the near-perfect absorber, the researchers employ gold nanoparticles, ...
Researchers have designed and fabricated an ultrasensitive plasmonic biosensor with the integration of atomically thin perovskite nanomaterials on metasurfaces. For that purpose, they used an atomically thin perovskite nanomaterial with high absorption rate, sandwiched between hexagonal boron nitride and graphene layers, which enables the precise tuning of the depth of the plasmonic resonance dip. This biosensor can reach an ultra-high plasmonic sensitivity for detecting small-molecule, ...
Terahertz (THz) frequencies, which occupy a middle ground between microwaves and infrared light, are seen as the future of wireless communications because they offer a higher bandwidth capacity for data transmission than currently used microwave radiation. Researchers have improved the photoconductive switch, a key optoelectronic element in THz technology, with a perfectly-absorbing photoconductive metasurface. The perfect absorption within this metasurface allows to make the active ...
Researchers have identified kirigami as an intriguing tool to create programmable mechanical metamaterials with unconventional mechanical and morphological responses. These reconfigurable metamaterials offer a new material platform to achieve dramatic changes of mechanical and optical properties, which are arising from dynamically tunable geometrical structures. A key feature of kirigami metamaterials is that they are conveniently cut when flat and then exploit local elastic instabilities ...
Researchers have used carbon dots, created from human hair waste sourced from a barbershop, to create a kind of 'armour' to improve the performance of cutting-edge solar technology.
