Showing Spotlights 17 - 24 of 27 in category All (newest first):
Plasmonic metasurfaces can be designed to achieve the singular-phase condition, yet this typically requires complex electromagnetic design and low-throughput fabrication techniques such as electron beam lithography. In a new work, researchers have developed a simple and robust planar singular-phase sensing platform for remote temperature detection, which does not require nano-patterning and exhibits singular-phase behavior due to the excitation of topologically-protected Tamm surface states.
Jan 18th, 2018
Chiral metamaterials with strong chiroptical properties are an interesting new platform for optical signal modulation. Although plasmonic super chiral fields have been successfully applied to detect the chiral structures of proteins, it has remained challenging to detect the structural handedness of drug molecules due to their small size and thinner film adsorbed on the surface of metamaterials. Researchers now have reported a new type of plasmonic chiral metamaterial by stacking two layers of identical achiral gold nanohole arrays into moire patterns.
Jul 25th, 2017
Compact optical components are crucial to realize miniaturized optical systems and integrated optoelectronic devices. Plasmonic metasurfaces - structured materials in 2D with rationally designed, subwavelength-scale building blocks - have drawn great interest because they can control light based on subwavelength structures. These planar devices are attractive for applications ranging from high resolution imaging to 3D holography. New work describes the design and prototyping of single-crystalline TiN plasmonic metasurfaces based on subwavelength hole arrays.
Jan 27th, 2017
Researchers have demonstrated that full-color 3D meta-holography imaging with extended viewing angles can be realized by a single layer of nanostructured metallic surface. In order to overcome the cross-talk among different colors that normally exists in current metasurface holography, the researchers introduced an off-axis illumination method to shift the holographic image in different colors and successfully reconstructed all visible colors in the imaging area. Taking advantages of the achromatic feature of the structure, the team also demonstrated full-color holography based on seven primary colors and 3D holographic imaging.
Nov 9th, 2016
Planar optical components are crucial to realize miniaturized optical systems and integrated optoelectronic devices. In particular, metasurfaces are of great interest for applications ranging from high resolution imaging to three-dimensional holography. Achromatic metasurfaces, which can maintain the same focal distance over a range of wavelengths, have been realized by engineering each subwavelength unit to induce an identical phase change at all wavelengths. However, the design method requires intensive computation. Researchers now have developed a highly efficient, universal algorithmic method based on evolutionary principles for the design of ultra-thin achromatic lenses.
Oct 28th, 2016
Researchers demonstrate for the first time a multifunctional biophotonic platform enabled by the multiband resonance peaks of the plasmonic moire metasurfaces. Benefiting from the multiband nature of moire metasurface and the near-field enhancement from the metal-insulator-metal configuration, the scientists achieved a dual-band metasurface patch with strong plasmonic resonances at both near-infrared and mid-infrared regimes.The plasmonic nanostructures support plasmon resonances at different wavelengths due to the gradient in size and shape.
Oct 12th, 2016
Graphene, one of the most exciting two-dimensional materials, has shown extraordinary optical properties due to strong surface plasmon polaritons supported by graphene nanostructure. Graphene metasurfaces show plasmonic resonance bands that can be tuned from mid-infrared to terahertz regime. These plasmonic devices can be used for biosensing, spectroscopy, light modulation and communication applications. Researchers now demonstrate for the first time an effective method to pattern large area graphene into moire metasurfaces with gradient nanostructures having multiband resonance peaks in mid infrared range.
Aug 16th, 2016
Poisson's ratio describes the fundamental elasticity of any solid. Poisson's ratio has been a basic principle of engineering for more than 200 years as it allows engineers to identify how much a material can be compressed and stretched and how much pressure it will withstand, before it collapses. Materials with a negative Poisson's ratio are relatively rare and it has recently become popular in referring to them as metamaterials - a group of materials that attain interesting or extreme properties via structure rather than composition.
Aug 3rd, 2016