Showing Spotlights 17 - 24 of 29 in category All (newest first):
Well-defined complex nanostructures for metamaterials with unique optical properties - such as negative refractive index, strong artificial optical activity and perfect absorption - are usually prepared by top-down approaches, including direct laser writing, multiple e-beam lithography, and membrane projection lithography. In a recent breakthrough, scientists have combined block copolymer self-assembly and an anodized aluminum oxide template to fabricate unique complex nanostructures over a large (centimeter) area.
Apr 26th, 2018
The metacanvas is a completely new generation of technology compared to all previous works. It is a tunable photonic devices based on vanadium dioxide that is lithography-free and fully reconfigurable. oth the patterns and the functionalities of the metacanvas can be arbitrarily reconfigured, which leads to many more degrees of freedom in metasurface design and functionalities. One piece of metacanvas is able to function as different optical components - hologram, phase-array, polarizer, modulator, etc. - at different times and on command, which has never been achieved in any of the previous VO2.
Feb 7th, 2018
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